This grisly exhibit houses skeletons and weapons from a devastating 14th-century clash.

The leathery remains of a woman who died in the 13th century now lie in a church named for her.

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

Historical figures from New York City's Catholic community reside in Midtown.

This ancient Irish landscape boasts hundreds of legendary ruins.

The remote graves mark the mysterious deaths of four 19th century explorers.

An eccentric priest's tribute to George Washington, this chapel tells the story of the American Revolution.

An eerie, derelict amusement park in Berlin.

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This Catskills museum preserves stumps from the earliest known fossil forest on Earth.

A hip bar decorated with walls of golden skulls.

Relics given to a Manhattan church to avoid seizure by the Italian government.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Church in Manhattan holds the bloody sock of Padre Pio, among with many other unusual relics.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

Series of storm drains connected to a dark urban legend.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

Perhaps the most scandalous statue of America's first president.