The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

This outpost of America's most popular fast-food restaurant is housed inside a palatial mansion.

An eccentric playboy's astounding natural history collection.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

A marvel of Byzantine engineering under the streets of Istanbul.