A Manhattan courthouse hides a small but scathing memorial to Holocaust injustice.

A celebration of capitalism in Midtown.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

New York City's smallest piece of private property.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

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

Elevated freight railway turned wildly successful urban park.

Try not to get slimed in Tribeca.

A crumbling hospital from the 1850s on Roosevelt Island.

At this Arctic outpost, get to know members of the indigenous Sámi community and meet their herds.

The world's northernmost aquarium looks like it has fallen over.

The world's most charming instant portrait studio also happens to be its smallest.

The great polar explorer is remembered in this far northern town, where he embarked on his final expedition.

Once America’s most beautiful army base, this abandoned military fort on the coast of Monterey Bay has been left to the elements.

A Faraday Cage protects cars from a nearby high-power transmitter.

A former ironworks that was the first UNESCO industrial site.

Once the local rulers had gone these enchanting ruins housed common folk in an almost real life fairy tale.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

The last bastion of Roman presence north of the Alps looms over a German town.

This noble mash-up in eastern Luxembourg is part Medieval, part Renaissance, all castle.

This tri-part waterfall is a little bit of fairytale beauty in the heart of Luxembourg's Little Switzerland.

This Luxembourg cave is covered in cryptic looking marks left by mining activity.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.