This unique building in the main square stands out among the city's typically Baroque architecture.

This 50-foot-deep sinkhole created in the 14th century is home to rare plants and fungi.

The site where a plot to assassinate Hitler was planned—and its conspirators were executed—is now a powerful memorial to the German resistance during World War II.

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

This natural hill rose another 130 feet from the debris and rubble added after World War II.

This old wooden funicular railway leads to a cemetery in the forest.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

Revitalization efforts converted a former U.S. military heliport into a sprawling urban park.

These caves secretly held national treasures during World War II.

An abandoned Byzantine fortress and notorious prison.

The hallucinogenic center of the ancient world.

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

This museum promotes informed contraception by documenting its often secret past.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

The 20th-century archaeologist was interred among the ruins of an ancient Roman city.

Gladiators battle and chariots race daily in the ruins of a once-great Roman city.

Just outside of Jordan's capital lies an ancient castle and intriguing caves dating back to the Copper Age.

A bathhouse from the second Islamic Caliphate decorated with frescoes of constellations, pleasure gardens, and naked ladies.

One man's labor of love, Amman's oldest home has become a time capsule with its doors permanently open to artists and guests.

This sprawling, formerly elite sporting complex in Amman, Jordan has become a local picnic spot.

An oasis of shade and color amidst the bustle of the old city.

The most gigantic, swoony, intimidating trio of fingers in all of antiquity.

This restored eighth-century palace is a shining example of ancient Umayyad architecture.

This exceptionally well-preserved ancient marvel also houses a small museum dedicated to Jordanian folk tradition.