Outdoor Dungeons

[FabulousFizban]

How would you go about creating a forest "dungeon" (or any outdoor dungeon) that PCs can work their way through? I'd like to have an actual layout instead of just saying, "you wander around the woods for four hours, here are some wolves," you know what I mean?

Basically, what is a good way to keep players moving through a prebuilt area that has "rooms" and "hallways" while they're outside and should have free reign to move about?

Just saying, "the foliage is impenatrably thick," would be seen as a challenge to undermine me (as it probably should).

[Grinner]

I'd start by not drawing attention to the impenetrably thick foliage. Instead state something like "There is steam babbling before you. Across the stream, you can make out a thin path running around a hill, but downstream, the woods open up into a clearing."

It helps to give them some kind of objective and points of interest to move between.

[Ozfer]

Never use impenetrable foliage. They will always burn it, and it totally ruins immersion. Just map out general points of interest and landmarks, describing it as they go.

[Jay R]

Impenetrable foliage is no more problematic than dungeon walls, in a world with Passwall, Dimension Door, etc.

There's no reason for them not to follow the paths most of the time, but when there is, let them do so.

Also, only put fun stuff on the paths and in the clearings. Clear-cutting loses its charm pretty quickly if there are no potential rewards.

[Frozen_Feet]

Outdoor dungeon is an oxymoron if I ever heard one. This is one place where you really ought to rely on realism rather than game logic: the forest is a god-damn forest, you can go to any one direction in there. Just don't expect to find anything particularly noteworthy if you stray away from known paths.

If your players want to turn the adventure in to "Lost in the Woods", let them. After 30 minutes of going around in circles around some rock, they'll be more than happy to stick to a trail.

[Xeratos]

How would you go about creating a forest "dungeon" (or any outdoor dungeon) that PCs can work their way through? I'd like to have an actual layout instead of just saying, "you wander around the woods for four hours, here are some wolves," you know what I mean?

Basically, what is a good way to keep players moving through a prebuilt area that has "rooms" and "hallways" while they're outside and should have free reign to move about?

Just saying, "the foliage is impenatrably thick," would be seen as a challenge to undermine me (as it probably should).

First off, what level party are you creating it for? If they're relatively low level (read: don't have access to world-altering magic yet), you can do things like put toxic plants in the forest (think of them as natural, self-resetting traps), put in ravines and gullies that they can cross if they make some good climb checks, but there's a rickety old bridge 200 feet away.

You could take them off the ground level and have them working their way through the canopy itself. You'd probably have to build some artificial structures to connect them like rope bridges, but if the ground is covered in deadly choker vine (escape artist DC 20 to get free of, only to run into another patch in the next 5 foot square), then those balance checks as the bridges swing back and forth become that much more dramatic.

Then there's the wildlife ("Stay away from that patch of forest, there's a den of dire wolves that way). That tree over there has a nest with some nasty, territorial, murderous, giant bird. Basically, my point is to give them reasons to stay within the defined areas of your forest dungeon, but if they choose to go off-path, know what the consequences are going to be, and make sure they know them too. I'm not saying you can't surprise them with something, just make it clear that there's a reason there's a path right here and that almost everyone stays on it.

On the other hand, if they're higher level, a regular forest isn't going to cut it. You'd have to go with something along the lines of the ancient, spooky, magically enchanted forest that dampens fly spells, that you can't teleport into or out of, and so on.

-----

Side point: I don't think setting a forest on fire is as easy as "I light my torch and stick it into this tree." Live wood doesn't burn all that easily. Yes, you can do it with enough persistence and fuel, but it's a fair bit of effort.

[Tridax]

...I thought you meant playing D&D outside.

But yeah, when the PCs end up in large areas, just give them objectives of where and how they go. The better if they have a map. If not, then you can describe the surroundings through their own POV and make assumptions of where they could go. On their way they may encounter some traps or animals. Or animals in traps. If a forest is big, it doesn't mean that the time spent on the jorney through it should be long. (Though the PCs may spend several nights camping)

[Kazemi]

Rather than creating rooms and hallways with traps and monsters wandering them, you're going to want to focus on the actual scenery. You don't want it to turn into only impenetrable foliage. Make sure you have adequate descriptions. Saying "There are trees everywhere" does not have the texture that generates immersion and true improvisation. You may want to look some stuff up online about dangers of the wilderness. For some reason, thinking of this reminds me of Minecraft and falling into a random lava pit in a jungle (don't do this to them, they're your friends).

They have to have a goal (such as getting to a temple, another town, the Lost Elven City, etc). Providing them a path gives you a "hallway" (famously dangerous or hidden, your choice). You could have some branching pathways if you choose, but I'd make sure each one leads to a different route and set of encounters, if only to have a contingency for when they go through one and backtrack to the other. Alternatively, they could just be using Survival to determine the proper direction each day.

After that, your "rooms" would represent unique portions of the forest. This includes, but is not limited to:

• Broken Path: Ravines, gaps, canyons, etc. These could have an intact bridge with a "toll" (or a "troll"), a falling apart bridge (a pitfall trap), or an outright broken bridge. Rivers also good, both with and without bridges. Keep in mind that they usually flow from high ground to low ground (depending on the latent magic in the area). This also gives the players a natural path with which they can find other creatures, since water will draw all sorts of living things.
• Signs of Monsters: Heavy Spider webs come to mind first, but broken trees could hint at a Giant, carvings on trees may hint at a lizardman tribe whose territory you're entering, etc. These precede the actual event.
• Resting Spots: such as springs, clearings, friendly wood-nymphs, etc. I try to include nice things for my players at a 1/3 or 1/4 odds (depending on how well they're doing). This can give them time to rest in actual peace. Of course, don't give them one every time. They should have to improvise in the jungle as well, especially if they leave the trail. Also keep in mind whether finding firewood should be difficult (who carries firewood in this game?)
• Survival: Play out some Survival rolls, some low-level stuff for him usually. If they run out of food/water they're going to need to pause while the Ranger hunts/forages for food or they'll have to settle for random herbs and plants and such. Of course, if he secretly rolls Survival then failures become an event of their own. Don't overdo it, though. Most of what they find should be all OK. Maybe 1-2 poisonings. If you want a "Poisoned Section" of the forest, make it obvious with bright blue mushrooms with thin purple stripes. Nobody would eat those and still have the right to complain.
• Random Encounters: a wolf attack, forest goblins stumble across the PCs while hunting and panic with arrows, elvish guard, etc. You might even have someone following the party, such as a bounty hunter, who attempts to engage them. At CR if they do it at full strength, but a lone Rogue would rely on engaging after they take a beating (in that case, add the Rogue to the CR of the encounter he's attacking after - the encounter will be slightly smaller to compensate).
• Fluff Encounters: These are things that literally have no form. A dozen eyes watching a player during his watch, but which vanish when he wakes up the party. A very loud roar coming from the jungle (different Listen rolls determine different directions and this may lure them off the path). Seeing a pair of way-above-your-CR Green Dragons duking it out overhead. By not giving them an answer to everything, it can add to the mystery of the jungle. When they try to chase something in this category down, give them something else instead (or nothing at all if that idiot charges blindly into the jungle without his party to attack the dozens of eyes - they just flee without sound and with preternatural agility).
• They've-Left-The-Path Contingencies: Several things for them to run into if/when they try to get off the path. This can include things like a mad druid, a small town (nest? warren?) of jungle Kobalds (with traps, of course, and possibly a dragon depending on their ECL), a wild Ranger (great for catching a player with one of those dangle-you-from-one-leg traps), etc. You'll want several, but in particular you want to think of where those events would lead to. The mad druid may tell them he's bringing them to the center of the forest, but he's actually bringing them to the Cave of Gigantic Centipedes that he tends. The Ranger may actually give them the right directions and lead them partway, although he won't go too close and leaves them to travel in the right direction with a good fair well.
• Moar Paths: If they're not on a path, then a path that does not quite travel in the right direction (NNE instead of plain North, for example). Traveling on a path is much easier and less accident/lava prone than traveling through even moderately thick foliage, but where does it lead? Is it worth it?

Also, I'd actually have the players roll their spot/listen checks in secret and in advance, rolling another set when you run out. Have them roll out of sight (into a box, for example) and record the numbers each person gets with their spot/listen modifiers. That way you don't alert them to "Make a Spot check!" warnings and you don't build up the paranoia that giving false alarms creates.

Edit: Also, keep in mind how thick the trees are. Does it count as Low Light? Full-blown Darkvision? I'd have it mostly normal during the day, but an Ominous Portion (spider webs and EVIL in the air) might drop down to Low Light.

PS: Hitting them with a thousand baby ballooning spiders would be interesting roleplay (they're like the size of a grain of sand, but they crawl everywhere). I'd make them harmless, since most of the players are likely to freak out.

PPS: I'd make the forest damp enough to be fire-resistant and I'd make it obvious enough (without spelling it out until they ask).

[Thrudd]

How would you go about creating a forest "dungeon" (or any outdoor dungeon) that PCs can work their way through? I'd like to have an actual layout instead of just saying, "you wander around the woods for four hours, here are some wolves," you know what I mean?

Basically, what is a good way to keep players moving through a prebuilt area that has "rooms" and "hallways" while they're outside and should have free reign to move about?

Just saying, "the foliage is impenatrably thick," would be seen as a challenge to undermine me (as it probably should).

When traveling in difficult terrain without a road or path, I implement a mechanic for determining if the characters get lost or go off track using survival/wilderness skill checks at regular intervals as long as they are not following a path or feature like a stream. You need to track walking time and direction behind the screen, and when they fail a skill check you secretly point them in a randomly determined direction up to 90 degrees off of where they were going before depending on how much they fail the check (and don't tell them the result of their skill checks, that would defeat the whole purpose). If you've ever actually walked in a overgrown and pathless forest without a compass, especially if it is thick enough to obscure your vision of the sky or overcast, you know it is really easy to go off in a different direction than you intended to. It isn't impassable, but it is slow going, carrying lots of gear makes it even worse. Having a druid or ranger in the party or someone with high skill ranks should make it easier, but you can make the skill checks for going off path as difficult as you want. Make heavy use of random encounters to make it exciting and dangerous to go off path (if you even have a path), so they will want to reach their goal more urgently. The terrain itself can have dangers equivalent of traps, as was mentioned above, with tangle vines, spiky carnivorous plants, etc, which will also randomly be encountered. You don't need a detailed map of the whole forest, but a general one that shows the overall size of the forest and the relative locations of the primary features. There may be monster lairs, a special grove or clearing, a hunter or hermit's shack. These areas might have paths or tracks near them that can be followed. Maybe one of the lairs actually has an interior large enough to explore, so you have a small section or two of more conventional "dungeon". The path leading up to the lair of a band of intelligent monsters or bandits may be booby trapped or have an ambush depending on how quiet the party has been. A magical grove might have wards and magical traps around it.
The purpose for them going to this forest and the manner they are able to approach it will make a difference. The terrain needs to restrict their approach to the forest in some way, like with a cliff or canyon, so that it has a predictable "entrance" area, and the goal areas are further in and not accidentally accessible if they approach from an unexpected direction. Also, is there something in the forest they are trying to find or retrieve, or are they just passing through on their way to another destination? You'll have to think about these things.

[FabulousFizban]

thanks guys, this is exactly the sort of stuff i was looking for and helps immensely.

[Seharvepernfan]

The OP got what he wanted, but I have stuff to say.

If the "forest dungeon" you are building is just a small part of the forest, like a few hundred yards/meters to a side, then you can design it like an actual dungeon. It could be an area with especially thick, interconnected trees, where the underbrush is somehow dangerous, and canopy is either very hard to get to, or is dangerous as well.

So, the "rooms" of this dungeon are clearings with no especially dangerous underbrush. The "walls" are the thick trees (thick both in girth and in how close together they are) or the dangerous underbrush. The "hallways" can be paths between the trees, root tunnels, tree branches, or holes in the trees. The "ceiling" is just the increasingly thick canopy, which can be traversed by climbing or flying.

The underbrush can be dangerous for a number of reasons. It might be especially tough and resistant to fire (as some trees/plants are), as well as barbed and poisonous to the touch. The players can go through it, with effort and/or expended resources, but they probably won't be able to go through all the "walls" like this. This should be made clear to the players.

The canopy can either be just a pain in the ass via simple logistics (hard climb checks, too much distance between the branches of separate trees to jump, etc), or it can be dangerous due to aerial enemies (maybe flying predators that for some reason can't or won't attack the players on the ground, or shimmerling swarms, flowers that release poison dust if somebody gets too close, etc.). Maybe dryads in the trees take offense to anybody climbing them, and attack the players unless defeated or persuaded not to.

Now, your players are going to think that you're just forcing them into playing through a "dungeon" in the normal way. So, only this small part of the forest should be like this, and there should be a reason for it that is known to the players (like, this area is home to fey lords/druids/elves who built it this way to keep people out). Also, if the players actually are capable of going through the "walls" or traversing through the "ceiling", you should let them - they gave their characters the right abilities or items to make this possible, so they should reap the benefits.

The "rooms" could contain land-bound animals/beasts/fey/plants/whatever, and treasure could be found on the corpses of those who came earlier, or in secret hidey holes and camouflaged caches left by the fey/druids/elves.

Alternatively, the "dungeon" could be the bottom of a chasm or valley in a forested area, so that the "walls" are the cliffs that lead out. You could also make a grid/hex map where each square/hex is a certain distance, and then you could populate each one with specific enemies/events/challenges/places/etc.

[Toofey]

I just wanted to throw in the classic Elvin Dungeon, the giant tree with platforms built throughout, linked by branches, elvin footbridges, tightropes, or less, impossibly high up. If there's areas you need to shield from access by flight you can do so with anything from dead magic zones, to razorsharp sword sized leaves blowing in the breeze around sensitive areas.

Canyons, perhaps with messas throughout make a good one as well, for check out some old westerns or "Red Dead Redemption" for some inspiration as to how this would work.

Another favorite of mine when I DM is a very hilly area, that in a flood becomes a bunch of isolated island, separated from each other by surging waters. So you can see the other "zones" of the dungeon but you can't reach them. It's a good one for lower levels but it breaks down pretty quickly once the party gains movement capabilities.

[FabulousFizban]

These are great guys, my campaign is on a forest/jungle heavy island, so ideas for specialized areas are very useful to me. It's a low level party now but we'll see where it goes

(the place is infused with chaos as im just flat out stealing the graygem, so radical terrain differances are fine & make sense)

[Kazemi]

The OP got what he wanted, but I have stuff to say.

If the "forest dungeon" you are building is just a small part of the forest, like a few hundred yards/meters to a side, then you can design it like an actual dungeon. It could be an area with especially thick, interconnected trees, where the underbrush is somehow dangerous, and canopy is either very hard to get to, or is dangerous as well.
/snip

This is actually kind of neat. It's going into my bucket of PC concepts: A druid whose goal is to make an effective Natural Fortress or Dungeon.

Also, keep us posted, Fizban! I'm curious to see how your group reacts to the various ideas. The more you know!

[Knaight]

Regarding dungeons - they are basically just points of interest connected in a particular way, and that can be duplicated easily enough for a forest. The town at the edge leads to the outskirts, the outskirts lead to a grove and a pond, the grove leads down into a ravine and into a deeper forest while the pond leads into the deeper forest and also a stream, so on and so forth. Then, transitioning between the areas requires various checks for movement.

[nedz]

A Druids glade with defensive planting which has been taken over. The Druids would like it cleared, but not by fire. This could have a maze like set of paths through dense forest and small 'rooms' off the side.

Heavy rain will dampen your PCs notions about burning the forest down any way.

A Fey type setting where locations can get surreal fast.

A series of passages inside a mountain peak with high ledges, rope bridges across chasms open to the elements, ledges covered in snow and ice, ...

[JustSomeGuy]

Anyone who has ever hiked will tell you, cutting through off-track can be a real pain - you can be crawling along at literally a quarter speed in some places, depending on vegetation etc.

The foting can be soft, clumpy, tangled roots, brush, soggy and uneven, which not only slows you down but can make you trip and injure yourself.

The mid level plants can be poisonous, thorned/barbed, tangled, thick enough to need cutting through, conceal predators and block lines of sight disorienting many experienced walkers.

The weather and conditions can make it worse - for example if it's raining, all you'll hear is the rain, snow will conceal everything underfoot, wind can drop all manner or canopy-level objects on you etc.

Following the natural game trails and clearings is a great idea, that's why most hikers and animals do it.

[Jay R]

I'm enjoying one fact about this thread immensely.

In every other area, the more recent versions of D&D have far more information. But the original white-box D&D had more pages devoted to designing the wilderness than the dungeon.

[JustSomeGuy]

Does anyone remember the adventure pack:

Set in the woods, there was a big mountain with a green dragon and a banshee (or something similar), i think you were looking for a daughter that had been abducted by a woodsman's boy (they'd actually run off together), and there was some involvement of some brownies or pixies or something (perhaps the woodsboy was a shapechanged one?), and they were trying to prevent a village/species war?

EDIT: you could travel anywhere you wanted, there was a massive area all hexmaped out and nudges towards the locations but all sorts of stuff out in the woods ( i think in one hex i heard banjos... back to the canoes!)

[nedz]

Anyone who has ever hiked will tell you, cutting through off-track can be a real pain - you can be crawling along at literally a quarter speed in some places, depending on vegetation etc.

The footing can be soft, clumpy, tangled roots, brush, soggy and uneven, which not only slows you down but can make you trip and injure yourself.

The mid level plants can be poisonous, thorned/barbed, tangled, thick enough to need cutting through, conceal predators and block lines of sight disorienting many experienced walkers.

The weather and conditions can make it worse - for example if it's raining, all you'll hear is the rain, snow will conceal everything underfoot, wind can drop all manner or canopy-level objects on you etc.

Following the natural game trails and clearings is a great idea, that's why most hikers and animals do it.

Yes, I'm sure you're right; but anyone who has ever run a game involving PCs will tell you that none of that stuff matters.
"The trees are very close, the underbrush dense and there are many thorns"
"We press on"
"It's very difficult"
"I'm very strong, I push my way through the thorns"

[JustSomeGuy]

Yeah, there is something of a difference between saying your character does something and actually putting yourself through it

"I can take a fireball, even at full damage roll i'd have x hp left"
vs.
"I can't drink that cup of tea yet, it's too hot!"

[DigoDragon]

There's no reason for them not to follow the paths most of the time, but when there is, let them do so.

Also, only put fun stuff on the paths and in the clearings. Clear-cutting loses its charm pretty quickly if there are no potential rewards.

This is how I'd construct an outdoor dungeon. Another neat idea is changing up what would be perceived as "treasure chests". A nice hollow in a tree, or a hole under a strangely marked rock make great points for the party to poke around to find goodies.

The party I DM'd through a forest had a warlock with fell flight. Maybe the warlock had an easy time getting over the dungeon to each clearing, but the rest of the party couldn't fly and they missed out on loads of secret treasures.

[TheStranger]

Some thoughts, most of which echo things that have already been posted, based primarily on a lot of backcountry and wilderness experience.

Start by mapping out the relevant section of forest. Place streams, swamps, cliffs, etc. in the relevant places. If you have trouble with geography, a quick and fun option is to go to google maps and pick an interesting section of the world to use (modified as needed). If possible, pick a spot you've been to but your player's haven't; that will make it really easy to create evocative descriptions and understand how everything relates spatially, and it's much easier to modify real-world places as needed than to make something up entirely. It's also kind of fun to create supernatural encounters that fit the feel of places you're familiar with. If you do it right, you'll get a very detailed, "realistic," and internally consistent place, and there's no reason for your players to suspect it's based on a real place. And there's absolutely zero chance of your players going somewhere you haven't "mapped out" yet.

Place your encounter areas within the forest, according to whatever logic you like.

Think about how your forest and its inhabitants interact. The goblins trekking from their camp to the pool under the waterfall have beaten down a path. The stream below the waterfall flows through the dryad's grove. There's a faint game trail leading from the grove into the cedar swamp.

Edit your map to connect encounter areas in other interesting ways. There's a dry streambed running from the mushroom circle up to the wolf's den. There's a crumbling stone wall near the ruins; if the characters follow it, they'll end up at the old well. The watchtower is on a ridge; if they follow the ridgeline they'll end up at the enchanted spring in the col. Most groups, if you put them in a clearing with a stream, a game trail, and a beaten path, will choose to follow one of those things - as long as you don't point out that the undergrowth is impenetrable everywhere else.

The undergrowth isn't actually impenetrable everywhere else. If they arbitrarily decide to march off through the underbrush to the east, look at your map; after struggling through mosquito-infested unpleasantness and maybe a random encounter, drop them into the next relevant area to the east. If they wander off your map (not a problem if you use the real-place method), presumably they're going east for a reason - roll with it.

That said, you can use cliffs, swamps, or other natural barriers to constrain your players somewhat, but only if you use them sparingly and make it clear that they're not absolute; you can struggle through the swamp if you're willing to move at a crawl, make some swim checks, and fight the occasional alligator, and you can climb the cliff if you're a good enough climber and want to fight the giant eagle that's nesting up there. You said they're on an island; that puts at least some outer limits on where they can go (though you can never rule out your players reenacting their favorite Gilligan's Island escape plans).

If they decide to fly (or climb the watchtower), tell them what they see. They'll probably aim for one of the interesting points anyway.

Since it's not an indoor dungeon, there's no way to guarantee that your players will go through it in any particular order, or that they'll visit everything. In a dungeon you can set things up so your players always get to read the inscription on the statue before they have to solve the riddle of the sphinx; you just can't do that outdoors. Don't assume that they'll find the diary in the abandoned cottage before they run into the amorous pixie. Accept that they might never stumble across the encounter with the polymorphed bear, no matter how much fun it was to design (but feel free to reuse it later on). It's hard to railroad outdoors; your encounters should interact in interesting ways, but they can't be dependent on each other unless it makes thematic sense for the characters to backtrack.

This also makes it hard to have a "boss" or "final" encounter to an outdoor dungeon, since your players might head there straight off, either by luck or design, and skip the vast majority of the "dungeon". One way around that is to have the paths, streams, ridges, and other "connectors" in the early part of the forest be very "spiderwebby," but have a few encounters in a remote part of the forest that are somewhat linear. Hopefully by the time your players get there, they'll be in the habit of following the paths you give them. Alternately, make a multi-part goal, so that they're likely to get through a big chunk of the forest before they get it all done.

This is a fun question, and I've always wanted D&D to support wilderness exploration better; I'll be watching this thread with interest.

Edit: Wow, that turned into a giant wall of text.

[Jay R]

Yes, I'm sure you're right; but anyone who has ever run a game involving PCs will tell you that none of that stuff matters.
"The trees are very close, the underbrush dense and there are many thorns"
"We press on"
"It's very difficult"
"I'm very strong, I push my way through the thorns"

"Fine you push through, getting caught on your clothes. They are slowly getting ripped to shreds, and you're moving very slowly. There is a hornet's nest ahead. If you keep going, you will disturb them and not be able to move away quickly. Something slithers past your foot; you can't see what kind of snake it is. Your boot gets caught in a tangle. Your sword is caught in a bramble, and will take a moment to get free. You see a rabbit foaming at the mouth."

et cetera.

If you've ever bushwhacked through rough country, you can easily keep inventing valid annoyances. If the first few hints don't work, go ahead and up the ante. The next hornets nest is on the other side of the tree, unseen until disturbed. I almost stepped on a timber rattler once, which cured me of bushwhacking.

[Kazemi]

"Fine you push through, getting caught on your clothes. They are slowly getting ripped to shreds, and you're moving very slowly. There is a hornet's nest ahead. If you keep going, you will disturb them and not be able to move away quickly. Something slithers past your foot; you can't see what kind of snake it is. Your boot gets caught in a tangle. Your sword is caught in a bramble, and will take a moment to get free. You see a rabbit foaming at the mouth."

et cetera.

If you've ever bushwhacked through rough country, you can easily keep inventing valid annoyances. If the first few hints don't work, go ahead and up the ante. The next hornets nest is on the other side of the tree, unseen until disturbed. I almost stepped on a timber rattler once, which cured me of bushwhacking.

I, for one, have never bushwhacked. Could you give a few more short examples of the stupid and annoying things that you have to deal with? If you have the time, of course.

[JustSomeGuy]

Not a massively relevant example, but kind of extreme:

On a military exercise, there was a guy we knew who drove the fuel truck, so he was often in and out of our location and on the road, living out of his cab. We got two days of maintenance, where the exercise stopped and everything got fixed, so he didn't have to go anywhere. He parked up next to a cosy looking hollow/depression with a big rock on one side, whic hhe proceeded to make into a little shelter/den, putting out his rollmat, sleeping bag, mosquito net, camp chair, poncho sheet etc.etc.etc. - it was a nice little homeyhouse for him. He stayed there for two days, and returned to the position repeatedly afterwards because he liked it so much. about 4-5 days later, we were moving on from the location so everything got packed up ready to move out, and as he is packing the last of his kit into his truck, a massive (5-6 foot? it was all curly and not near a tape measure) rattlesnake slithered out from under the rock he'd lived by for nearly a week!

[TheStranger]

I've bushwhacked plenty. The annoyances depend on terrain; in my part of the country, there are no rattlesnakes. However, there are more than enough waist-deep swamps for anybody. There are also hornets, dense, thorny areas, small cliffs, and so on.

The thing is, none of these things is an impassable obstacle. In the real world, most reasonable people follow trails because it's a lot quicker and more enjoyable. But in most cases, a sufficiently determined person can go around, over, or through most obstacles and continue on their way. This is especially true when the only hardship involved is saying that you do it.

Player: "I wade through the chest-deep, leech-infested, foul-smelling mire."
DM: "Are you sure? You'll have to make Survival checks to avoid sinkholes under the water, and it's going to be really slow going. And there are alligators."
Player: "Yeah, I've got +25 to Survival, and I can take an alligator."
DM: "Don't forget the poisonous snakes."
Player: "Good fort save. Oh, and if it's chest deep, can't I just swim?"
DM: "It smells like a sewer."
Player: "I'm a barbarian. Nobody will notice the difference."
DM: "No reasonable person would do something like that."
Player: "Duly noted. Can we start now?"

At which point, the DM has to either flat out say "no" or go forward with the appropriate skill checks and/or combats. Sure, most people would wisely take the path around the swamp in real life. But only by DM fiat can you make it an absolute barrier.

EDIT: And that's completely leaving out things like the woodland stride ability, which explicitly remove some of the obstacles to real-world bushwhacking.

[Wardog]

"Fine you push through, getting caught on your clothes. They are slowly getting ripped to shreds, and you're moving very slowly. There is a hornet's nest ahead. If you keep going, you will disturb them and not be able to move away quickly. Something slithers past your foot; you can't see what kind of snake it is. Your boot gets caught in a tangle. Your sword is caught in a bramble, and will take a moment to get free. You see a rabbit foaming at the mouth."

et cetera.

If you've ever bushwhacked through rough country, you can easily keep inventing valid annoyances. If the first few hints don't work, go ahead and up the ante. The next hornets nest is on the other side of the tree, unseen until disturbed. I almost stepped on a timber rattler once, which cured me of bushwhacking.

If the going is that tricky, and if their wilderness skills are not high enough, then it will probably be quite difficult for them to keep going in a perfect straight line. Whether because they simply can't navigate, or because the undergrowth is slighly less dense, or the ground slightly leveler in one direction. Which means you can probably "steer" them back towards the direction you want them to go, without them them even necessarily being aware you are doing it.

(Besides, "we spent ages tramping/hacking through the forest, and ended up back where we started" has been a trope since forever).

[nedz]

"Fine you push through, getting caught on your clothes. They are slowly getting ripped to shreds, and you're moving very slowly. There is a hornet's nest ahead. If you keep going, you will disturb them and not be able to move away quickly. Something slithers past your foot; you can't see what kind of snake it is. Your boot gets caught in a tangle. Your sword is caught in a bramble, and will take a moment to get free. You see a rabbit foaming at the mouth."

et cetera.

If you've ever bushwhacked through rough country, you can easily keep inventing valid annoyances. If the first few hints don't work, go ahead and up the ante. The next hornets nest is on the other side of the tree, unseen until disturbed. I almost stepped on a timber rattler once, which cured me of bushwhacking.

We have very benign wildlife in this part of the world but I have almost broken my leg on a couple of occasions when I suddenly sank to my knee in a hidden hole.

(Besides, "we spent ages tramping/hacking through the forest, and ended up back where we started" has been a trope since forever).

It's not just a trope: It is very common in Forests.

[TheStranger]

If the going is that tricky, and if their wilderness skills are not high enough, then it will probably be quite difficult for them to keep going in a perfect straight line. Whether because they simply can't navigate, or because the undergrowth is slighly less dense, or the ground slightly leveler in one direction. Which means you can probably "steer" them back towards the direction you want them to go, without them them even necessarily being aware you are doing it.

(Besides, "we spent ages tramping/hacking through the forest, and ended up back where we started" has been a trope since forever).

The DC to not get lost in the woods is only 15. Almost any wilderness-oriented character can make it by taking 10, often from level 1. Even with a few circumstance penalties, it's a pretty trivial check anywhere above first or second level, especially with synergy bonuses. As it should be; getting lost just shouldn't be a worry for any halfway competent ranger or druid. If nobody put any ranks in survival, it's a valid concern, though.

I'm not saying there aren't difficulties associated with bushwhacking, but in D&D these tend to be abstracted down to skill checks. I'm all for making the players make those checks, or having backcountry encounters, or slowing down travel time, or whatever. But for all but the lowest-level parties, these aren't insurmountable obstacles, and the PCs are probably capable of going off-trail if they choose unless the DM makes bushwhacking arbitrarily hard in ways that, IMO, amount to DM fiat.