As the Dead Sea continues to deplete, massive sinkholes open along its banks.

The remains of this ancient fortress atop a manmade hill look as though they were built into a volcano.

A "miracle" that seems to produce more holy fistfights than holy revelations.

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

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

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

The bears of Bern have been a city highlight for over 500 years.

The 20-mile causeway that separates the Netherlands from the sea.

A public urinal so pretty, it was declared a national monument.

The world's tallest bridge is also possibly the most elegant.

2300-year-old Roman road connecting the empire.

The only visible reminders of an elaborate engineering project that kept the tower from reaching the tipping point.

An Albanian monument to the Communism that nearly crushed the country is now a crumbling wreck.

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

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

Single runway interrupted by a busy road that cuts across its middle.

Mosaics, storks, and brothels—this ancient city has it all.

The other side is actually green.

Thousands of narrow alleyways in an ancient medieval city make up what's believed to be the world's largest car-free urban zone.

Traditional 11th-century outdoor tannery.

Displaced highlanders would take shelter from the wet Scottish climate under the large walled bridge at Glasgow Central Station.