One of the world's tallest flagpoles.

Bombed and burned, this monument represents the often controversial ties between Vietnam and Cambodia.

A secluded, little-known temple hidden amid the dense jungle.

The capital of Cambodia is named after the hill on which this ancient temple complex stands.

Many people don't realize there’s a lot going on in—and below—the world’s tallest triumphal arch.

The ruins of the bathhouse used by the ill-fated last Aztec emperor still lie in Chapultepec Park.

The only castle in North America to ever house European sovereigns.

An elaborate Mayan city shrouded in alien conspiracy revealed the tomb of Pacal the Great.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Once home to an aristocratic family and a workers' organization, this intricately tiled building now houses a chain restaurant.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

Remnants of cone-shaped fascist bomb shelters in Milan.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

This endearingly discomfited urinating statue commemorates the sneaky pees had by us all.

Legend has it that Napoleon Bonaparte fell in love with this Gothic church.

Travelers who fall victim to this mermaid's charms are destined to stay in Užupis forever.

Latvia's symbolic mountain-shaped national library is home to millions of cultural tomes.

The oldest housing complex in Riga is a mini timeline of architectural trends.

Once part of an ancient international harbor, it's now an all-you-can-eat shrimp buffet for flamingos and other water birds.

This no man's land slicing through the island is strewn with abandoned relics of another time.