Best spellcaster class and subclass for planar knowledge and planar travel?

[Vorenus]

I'm trying to create a character that specializes in knowledge of the planes, planar portals, planar entities, etc. Something like the Horizon Walker for Rangers, but for a primary spellcaster class--either Wizard, Sorcerer, or Warlock. (I'm not interested in Bard, but if I'm missing something obvious about Bards, please let me know.) Specifically not Clerics or Druids--only arcane magic for this character, please.

So what are the best class and subclass combinations for an arcane spellcaster who specializes in the knowledge and power of the planes? And what are the reasons that make that combination shine?

Thank you.

--Vorenus

[RogueJK]

I think Lore Bard actually fits the bill nicely. You have an overtly knowledge-based subclass that can use Magic Secrets for grabbing non-Bard plane-related spells. Plus you'd have Expertise in skills like Arcana to reflect your deep knowledge of the planes and planar entities, or Investigation/Perception to more easily locate portals.

It's likely a better fit than any of the Sorcerer/Wizard/Warlock options. Conjuration Wizard would probably be next, as an INT-based scholarly class that specializes in the spell school that governs plane/teleportation-related magic, but it's a distant second to Lore Bard in my mind.

[Kane0]

Lore or Spirits Bard
Clockwork or Divine Sorcerer
Fiend or Genie Warlock
Conjurer or Diviner Wizard

[Arkhios]

Horizon Walker (ranger).

[Vorenus]

Thank you to everyone for your suggestions.

[Vorenus]

After kicking this idea around for a while I still haven't found something that really clicks with me. I'd like to ask if people want to propose any homebrew Wizard subclasses focused on planar lore and planar travel. Feel free to use this thread to share your homebrew ideas.

[LordShade]

2e Planescape had some kits related to planar travel and knowledge. I vaguely remember that the wizard kit had an ability to punch through magic resistance and also had the ability to disregard some planar modifications to spellcasting (e.g. divination spells don't work properly on Acheron.)

The 5e version should have the ability to remove advantage on enemy saves due to magic resistance and the same spell key ability (if used in the campaign).

I would do a Knowledge Cleric 1/Wizard X. Knowledge Cleric is for Expertise in Arcana and Religion, which covers the planar knowledge. Regular wizard movement spells should cover travel.