Let's share some fantastic, bizarre, and weird real world locations that would make perfect fodder for #ttrpg !
My own contribution is "Christ of the Abyss", a bronze statue of Jesus that was deliberately sunk into the ocean off the coast of Italy in 1954. Two other statues were cast from the same mold later on, and sunk at Grenada and Florida.
I find the very concept of religious statues being sunk into the ocean fascinating - and, of course, in fantastic worlds people might have an easier time visiting such statues. Perhaps they have acquired some magic that allows them to breathe water for some time, or perhaps they are naturally amphibious. Or natural water breathers - perhaps there is some trade deal with surface dwellers where land-based religious items are created for aquatic civilizations that they cannot manufacture themselves.
What other such weird locations do you know of?
Here is a neat bit of ancient technology: A qanat.
A common problem in arid regions is how to get enough water for your irrigation needs. Digging wells is one possibility, of course, but the water table might be far beneath the surface.
However, the neat thing about the water table is that it runs parallel to the surface - so if the terrain rises up and forms a mountain, the water table will rise up beneath the mountain as well. Thus, you can tap the water within the mountain simply by digging a tunnel into the flank of the mountain.
Which isn't exactly a trivial undertaking, of course. Still, some qanats in the Middle East have been in use for several thousands of years.
And for #TTRPG , such qanats represent a good entrance to the "Underdark", or whatever the local "Realms Below" are called - or vice versa, and monsters might emerge from them. And what happens if a qanat suddenly ceases to bring water? Naturally, some daring adventurers have to go in there and solve the problem, or else an entire community might starve!