A secretive collection featuring objects that were designed specifically for U.S. intelligence operations.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

A beautiful geyser under environmental threat.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

The highest point in Arizona is an oddly snow-topped peak within the otherwise arid state.

See massive fossils that are over 200 million years old in northeastern Arizona.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Erotic art covers the walls of the largest ancient pleasure palace.

Ancient snack bar of the Roman Empire re-opened.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Go inside to really appreciate this 500-year-old technological masterpiece.

A whale rib was used to advertise the store by the arch that offered exotic goods from far away.

Pilgrimage site for star-crossed lovers.

This stunning concert hall has become a symbol of Iceland's national recovery.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This newly renovated Soviet-era outdoor exhibition center is bigger than the principality of Monaco.

Gargantuan home of Russian science.

Stalinist skyscraper built with help of cryotechnology.

The tallest hotel in Europe.

World's largest bell sits on the grounds of the Kremlin in Moscow.