Light still pours into the ruins of this ancient Islamic observatory.

Controversial site of what could be Europe's first pyramid.

A wellspring of natural Viagra found in Bosnia.

A field filled with carved medieval tombstones called stećak.

This abandoned Olympic skiing facility still bears the scars of the Siege of Sarajevo.

This top-secret nuclear bunker hidden in a Bosnian mountain has been converted to a modern art exhibition space.

The sad remains of a monument to martial arts legend and movie star Bruce Lee—in the middle of Balkans.

This abandoned airplane hanger is said to have once been a top secret launch facility.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

Inat Kuća, or "House of Spite," is more than just an oddly named restaurant.

This surreal memorial/cemetery is a necropolis of crumbling stonework and puzzle-shaped headstones.

The spectacular history of spectacles on display.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

The world's oldest Jewish library was founded by Sephardic Jews in 17th century Amsterdam.

This cheese shop also houses a museum devoted to Dutch dairy.

A simple plaque remembers an act of WWI terrorism that obliterated an island and forever scarred the Statue of Liberty.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

Quirky castle designed by the American actor best known for portraying Sherlock Holmes on stage.

This small-town Connecticut restaurant gives each diner a free book from its vast library.

This tiny New Jersey village has lived many lives but seems determined to remain a ghost town.

A storefront museum in Asbury Park honoring the Jersey Shore’s deep history of mystery—including the Jersey Devil.