The world's first clock to use set theory as a measure of time required the invention of a new light bulb just to maintain its obtuse measurements.

This wrecked airplane has been sitting on a black sand beach since the 1970s.

These concrete domes were installed on an Icelandic bluff to honor a very specific musical tradion.

A trio of hidden hot tubs takes advantage of Iceland's natural geothermal vents.

The massive cave church of Cairo's Zabbaleen community is one of the largest Christian churches in the Middle East.

These warring psychedelic crags commemorate an unsuccessful military operation.

This former steel and coal plant is now a neon-lit industrial fantasia.

Boats must transform into railroad cars to navigate this Polish canal.

After the famous composer died in Paris, his sister snuck his heart out of the country to honor his wish that it be buried in their native country.

On Japan's Tashirojima Island, cats are king.

An isolated dive site teeming with cnidarians.

Right up until the 20th century this network of man-made caves was the biggest village in Eastern Armenia.

Crammed into a Baltimore row house is an oddities shop that sells everything from skulls to dead insects.

Despite being considered a thoroughly American sport, basketball's oldest surviving playing field is found in the basement of a Paris YMCA.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

This picturesque archeological site looks like it was pulled straight from a fantasy novel.

This century old flensing port is a remnant of a culture for whom whaling is still legal.

The largest lake in the Faroe Islands seems to be held hundreds of feet above sea level thanks to an optical illusion.

The site where one of the most famous poems of World War I was composed is preserved to honor the legacy of the work.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

Thirteen sculptures in central Moscow graphically depicting vices of the modern world.

This collection of odd proofs of concept is like taking a walk through the imagination of a Victorian engineer.

Nestled on the banks of a river in Nuremberg is a small museum that was once home of the city's official executioner.