how large is the dark lake?

[Camman1984]

I am playing out of the abyss and don t want to look at the book but want to get an idea how big the dark lake is? the travel times by boat are pretty long but boats are sluggish.

am considering using my familiar as a carrier bird to deliver messages and wondered if that would be possible, hawks and ravens can both do a few hundred km in a day, doves can do 1000km in a day so it is potentially possible

[lunaticfringe]

It's not so much a lake as an area with a lot of interconnected waterways & there is no wind just rowing which probably explains long travel times. The old school sources list the cavern as 100 mi across with nothing I could find for 5e specifically.

[Finback]

am considering using my familiar as a carrier bird to deliver messages and wondered if that would be possible, hawks and ravens can both do a few hundred km in a day, doves can do 1000km in a day so it is potentially possible

Can your familiar see in the dark as well?

[Camman1984]

the owl has 120ft dark vision, didn't even consider that issue thanks :)

owls have decent speed but I can't find a lot of information about their endurance. they can glide silently for a long time but that's about all I can fun.

[Contrast]

According to the findings of 'Long distance migratory movements and habitat selection of Snowy Owls in Nunavut' by Mouland et al. (2008) an owl may be expected to travel 20-30 km (15-20 miles)/day typically in the wild. Of course your bird isn't a wild bird.

In game terms the owl has a flight speed of 60ft. DMG says to calculate a daily rate you travel ((speed/10)*(hours of travel, typically 8)) miles. So assuming your bird flies for 8 hours that would be 50 miles.

D&D is a weird hobby sometimes.

Of course really with this sort of question the only real answer we can give is that it is entirely up to your DM how viable this is. Keep in mind the owl probably won't have a way of actually finding its way over that distance unless it already knows the terrain well.