Unusual hexagonal rocks formed by cooling lava named for their resemblance to traditional Japanese tatami mats.

The deepest sinkhole in Central Europe comes with a grisly tale and an unusual nickname: “The Stepmother Abyss.”

Surprisingly aquamarine waters fill deep lakes formed at the end of the last ice age.

A tribute to Ponce de Leon's supposed quest for eternal youth.

The library of every book lover's dreams.

Who needs fancy modern water slides when this giant North Carolina rock works just as well?

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

One of Ireland's most infamous prisons for rebels including men, women and children.

An vast warehouse of everyday treasures in Berkeley, CA.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

The 953 windows undoubtedly make this the world's most beautiful screened porch.

A crumbling hospital from the 1850s on Roosevelt Island.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

A museum dedicated to the alleged Roswell Incident.

A snapshot of the city's fascinating voodoo culture.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

An alternate history park where the Union Army loses the war... to dinosaurs.

An oasis of calm amid the chaos of the boardwalk, the museum traces the heritage of this beloved beachside amusement park.

This wondrous waterfall rushing down a green-covered mountain wasn't discovered until 2010.

The name of this tiny pocket park tucked between two buildings on Manhattan's Upper West Side is Latin for its location: "seventy-one."

The celebrity luchadores of La Paz are tough ladies in traditional petticoats and braids.

An astounding annual light display honors the victims of one of Japan's most devastating earthquakes.

A "sinister, whimsical, tacky, and really orange" public art installation hidden under a Seattle bridge.

This chain of artificial lakes was an ideal test ground for the aircraft that would carry the "bouncing bombs" used by the WWII "Dambusters" squad.