Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

A man's head is enshrined beneath a statue near the first building constructed for the modern Olympic Games.

These artifacts were discovered during the construction of the airport, with some dating back to the Neolithic period.

A 19th-century politician who died after walking home in a blizzard is honored with this Manhattan statue.

This monument to a veteran of the Mexican-American War is one of only two in Manhattan that serve as an actual mausoleum.

Cryptic messages embedded in the New York City sidewalk.

Mysterious 500-year-old tapestries depict a unicorn hunt.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

This small chapel holds the mummified heart of one of the heroes of the Greek Revolution.

The oldest cemetery of modern-day Athens blends the modern and ancient worlds.

This legendary city has been a tourist attraction for centuries.

This 15th-century island fortress later served as home to the executioners no one wanted to live near.

The ruins of an ancient Roman tomb hidden in the basement of a trendy clothing store.

Where commuters walk through remnants of an ancient Greek necropolis.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

The hallucinogenic center of the ancient world.

This famous archeological mystery may be an ancient example of movable type.

This mystical orb covered in strange symbols is thought to have been used in ancient Greek magical rituals.

The only surviving choragic monument is a trophy awarded in 334 BC for the winning dramatic chorus.

An ancient octagonal weather station named for the eight Greek gods of wind.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

The fine fabric handwoven at Biltmore Industries was once coveted around the world.