This hidden collection of everyday objects illustrates life within communist Poland.

A 20th-century picture show in 3-D.

The world’s narrowest house makes for an awkward, four-foot-wide living space.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

After the famous composer died in Paris, his sister snuck his heart out of the country to honor his wish that it be buried in their native country.

A national collection of Communist-era musical posters.

A hidden art gallery in an abandoned Warsaw fort.

Warsaw's fantastically preserved gasworks...almost.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

This legendary city has been a tourist attraction for centuries.

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

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

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

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

A spectacular cave and a beguiling lake.

The hallucinogenic center of the ancient world.

150 or so scrounged-up lamps, chandeliers, and lanterns light up this alley in central Athens.

These ancient ruins hide in plain sight next to a dessert shop.

There are many Byzantine-era churches still standing in Athens, but this is the only one with a 2,500-year-old column rising through its roof.

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

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

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

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

This ancient hydrological marvel is now the base of a modern outdoor cinema.