An ancient iron pillar in Delhi that seems to be rustproof.

An imperial fortress city that incorporated cultural elements from the entire Mughal empire, only to be abandoned the year it was finished.

A blooming house of worship for the masses.

The world's second-largest sundial, made entirely out of stone.

The 953 windows undoubtedly make this the world's most beautiful screened porch.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

A local prank turned town icon.

This stately 19th century library pushed architectural boundaries at a time when the public library movement was just taking off.

A meteorite-bounded town in Bavaria.

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

One of the only spherical 19th century gas containers left today.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.