Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

A neo-gothic statue modeled on German Emperor Kaiser Wilhelm II, which had its distinctive mustache shaved off by Nazis in World War II.

This small chapel built into rock is the oldest place of worship in Luxembourg.

This 12th-century castle majestically overlooks the city and the beautiful Mosel River valley.

A swath of France so devastated by war it is still forbidden to go there.

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.

Site of one of World War I's most horrific scenes.

Its buzzing collection honors vibrator history.

The Cathedral of Salamanca has a number of unusual carvings but none so surprising as a modern astronaut.

The facade of this 16th-century building is decorated with carvings of 300 seashells.

In Spain, the ruins of a Roman military camp sit along a flooded section of a river.

The atmospheric ruins of a historic church can be found on a hill above the city of Oviedo.

Two large posteriors in one giant statue.

A statue honoring the tragic heroine of a Spanish literary masterpiece.

The much-loved protagonist of famed Argentinian comics can be found sitting on a park bench.

The surviving remnants of a destroyed medieval church now stand in a public park.

This 19th-century fountain's namesake animal isn't what you think it is.

Giant topiary dog once played a role in a terrorist bomb plot.

Somber memorial to the May 10, 1933, book-burning which took place on this spot.

There has been an astronomical clock on this spot since the 14th century.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

One of Malta’s most popular beaches features a seemingly out-of-place statue of the Virgin Mary and baby Jesus.

Spectacular secluded inlet with clear waters flanked by limestone cliffs.

These clocks tell time in a theological sense.