Built in 1512, the oldest cathedral in the Americas.

The final resting place of Christopher Columbus - or possibly someone else.

The first official clock in North America, it kept time for the Spanish government of Santo Domingo.

This trio of Dominican cave lakes comprise a colorful biosphere of natural life.

"Mock all and sundry things, but leave the saints alone."

Historic Hull Street was actually the first street with a proper name in the Boston area.

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

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Secret North Korean passage discovered below the world's most dangerous border.

Ho Chi Minh's perfectly preserved body has been on display here since 1975.

Ha Long Bay's "Cave of Surprises" houses a popular phallic rock formation.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

France's most famous cemetery, with some of its most curious tombs.

The celebrated eyesore created by starry-eyed sweethearts.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

One of only two commuter aerial tramways in the United States.

A little lighthouse in New York City, surrounded by mysterious stories of insanity-driven construction.

A former insane asylum despised by Nelly Bly and Charles Dickens is now fashionable apartments.

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.

The most confusing clock in New York.

This exemplar of modernist architecture is meant to captivate and inspire students of the Cooper Union.

Climb inside an iron crystal magnified 165 billion times its normal size.

Theme park featuring miniature replicas of European monuments.

The tiny Belgian town's ancient version of Mardi Gras involves eerie wax masks, sticks for warding off evil, and ostrich plume hats.