I quite like these channels:

Rambalac for walks around Japan https://www.youtube.com/c/Rambalac

HKSAMA for train rides in Japan https://www.youtube.com/c/HKASAMA

Nomadic Ambience for walking in quite a few places around the world: https://www.youtube.com/c/NomadicAmbience

And Sound Traveler for binaural walks around the world: https://www.youtube.com/c/TheSoundTraveler/videos

Destin from Smarter Every Day has been getting a bit of attention on Hacker News lately, so it might be interesting to know that Sound Traveler is his project!

https://www.youtube.com/c/ProWalks is good for Europe