Baldwin Street, Dunedin, New Zealand - "world's steepest street". Granted, not very walkable, but a curiosity nonetheless.

u/sonderewander — 12 hours ago

Aizu Sazaedo Temple, Aizuwakamatsu, Japan - an internal double-helix where you can ascend and descend without crossing paths [OC]

u/sonderewander — 12 hours ago