This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

An underwater city for the dead.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

An abandoned water sports stadium that has become a haven for graffiti and decay.

12,000 sq. ft. museum tracing erotic art from antiquity to modern times.

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

The behemoth beasts engaged in an epic battle is the second-tallest statue in the contiguous United States.

This abandoned shopping arcade has new life as an art installation.

A crushed gate and giant bronze head serve as a reminder of Greece's fight for freedom.

The site where hundreds of Greeks were tortured by the Nazi secret police is now a cosmetics store.

One of the greatest collections of coins in the world is housed in the former mansion of an archeological pioneer.

A grotesque collection of wax limbs depicting the symptoms of venereal disease.

Legend says this sacred tree was a gift from goddess Athena.

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

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

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

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

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

A spectacular cave and a beguiling lake.

Monasteries on rock pillars, once accessible only by frayed ropes.

The hallucinogenic center of the ancient world.

Designed by famed 20th-century architect Cass Gilbert, the future of this abandoned 1908 rail station is currently in limbo.