This legendary city has been a tourist attraction for centuries.

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

Where commuters walk through remnants of an ancient Greek necropolis.

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

The remains of a sunken military ship wreck visible through clear water.

Island wonderland for communist autocrats.

The only gulag ever to exist in socialist Yugoslavia.

The Renaissance-era courthouse is a relic from the fortified town's centuries of Venetian rule.

The "dragon babies" of southeastern Europe.

This massive subterranean fissure is known as the "underground Grand Canyon."

A miniature train-ride through Slovenia's largest cave system.

This Croatian computer club features such gaming relics as the infamous Virtual Boy and an 8-bit Pacman machine.

In the world's oldest university is a stunning 17th century anatomical theater carved from spruce.

Pilgrimage site for star-crossed lovers.

Two stone columns flank the grand Venice square, but there were supposed to be three.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

This London plaque marks the spot where David Bowie's famous alien made his debut.

A portly statue of a golden boy commemorates an unusual cause of the Great Fire of London: the sin of gluttony.

The London statue that imitates passersby.

Ship-sized kinetic sculptural fantasy.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

Eighty million natural history specimens call this gargantuan museum home.