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

Spain's largest bullring offers a unique glimpse at architecture and history.

This former charity hospital for elderly clergy houses some of Seville’s most treasured paintings.

The final resting place of the great navigator, or maybe his brother.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Reminders of the Battle of Berlin still scar the railway.

Cold war icon and onetime "hole" in the iron curtain.

A restaurant and observation deck built in a unique broadcasting antenna.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

The most visited, and possibly most controversial, museum in Germany.

This strange statue features a bust of the famous composer plopped atop a woman's body.

Ugly 18th-century dwarf statues living in a perfectly landscaped Austrian garden.

Is this 47.7-mile stretch of highway the longest straight road in the United States?

A half-size replica of the World Trade Center towers above Tulsa.

Sid Vicious famously punched a hole in the wall of this iconic music venue.

The storied steakhouse is the last in a long line of Lebanese-owned supper clubs in Tulsa.

The fifth tallest statue in the United States is a shirtless monument to the oil worker.

This historic theater's pipe organ still accompanies silent films just like it did in 1929.

Standing at 21-feet tall, this space cowboy adds to the legacy of Route 66's muffler men.

The collection is housed in an exquisite mansion that makes you feel like you've been transported to an Italian villa.

This former mining town was named the most toxic town in America.

The Ozarks' strangest dwelling.