Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

This retro, UFO-like structure is a remnant of the Soviet-era circus.

An outstanding piece of retro Sci-Fi architecture built into a sacred mountain.

South Korea's women of the sea have completely flipped their society's structure by becoming revered fisherwomen.

South Korea's only sex-themed park.

A theme park made of glass, from the gleaming books on the shelves to the crystal fish in the mirror lake.

A colossal floating restaurant built to look like a ancient Chinese imperial palace.

A fifth-century temple improbably built into the side of a cliff.

A tribute to an iconic act of defiance from the Croatian War of Independence involving a small car.

Longest fortress system anywhere in Europe.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

The tangled roots of a giant banyan tree have fully reclaimed the ruins of this abandoned warehouse.

A secret passageway from World War II is now a quirky pedestrian shortcut.

This attraction is part anthropological journey and part amusement park.

The world’s largest work of glass art hides in this stunning Taiwanese subway station.

Once a prosperous mining village, this tiny Taiwanese town is now overrun with cute cats.

Grandpa Rainbow felt the neighborhood needed some color, so he picked up a paintbrush and went to work.

An abandoned swimming pool decays on the outskirts of Berlin.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

An eerie, derelict amusement park in Berlin.

This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

A fascinating insight into daily life in the Eastern Bloc.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

When German-Iraqi relations broke down, this embassy was vacated post haste.