Hidden just under the waters around this Turkish island are the ruins of a once great city.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

This church houses the tomb—but not the remains—of St. Nicholas, the likely progenitor to Santa Claus.

This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

These ancient ruins include a stadium dating back to 400 BC.

The alleged house of the Virgin Mary is tucked away in a park and nature preserve on Mt. Koressos in Turkey and is holy to both Catholics and Muslims alike.

This crumbling medieval basilica once attracted pilgrims by the thousands to collect a miraculous dust that formed above the saint's tomb.

An underground network of massive stone arches and their skylit vaults support ruins of portico structures above.

Rediscovered underground chapel is one of the best examples of Gothic architecture in Vienna.

The beautiful baroque library of the Hapsburg empire.

On this spot in 1989, nearly a thousand people broke through the Iron Curtain.

The world's largest historic armory was established by independent citizens to defend themselves from the wars of larger forces.

This lush, scenic spot was carved by the turquoise waters of the Radovna.

From a 1930s bathing beach to a 1970s dumping ground, this stretch of Buenos Aires is now its largest and wildest reserve.

This solitary convex mirror sculpture at an abandoned ferry station at the edge of a fjord reflects the scenery back at the viewer.

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.

This roadside attraction looks like a flying saucer parked atop the tundra.

World's strongest whirlpool.

A hidden highland of peaks and pastures, largely unchanged since medieval times.

This boat represents the promise of undiscovered territory, a dream of hope, and progress and freedom for Iceland.

A time capsule from 1934 Rhodesia, showing the grace and disgrace of a bygone era.

An enchanting rocky island of scraggly baobabs surrounded by an ancient sea and sprawling salt pans.

Spanning over 10,000 square miles, this ancient salt pan is one of the largest on the planet.

There is only one place in the world where the corners of four nations come together.