A charming "tea atelier" hidden away in Greenpoint, Brooklyn.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Hidden in one of New York's oldest subway stations is the final remnant of the site of the bizarre Shakespeare Riots.

Leaf through over 30,000 artists' sketchbooks in what may be the world's largest collection of doodles

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

This impressive mansion in Vinegar Hill has some mysterious details in its architecture.

The Underground Railroad passed right through this historic Brooklyn Heights church.

A dark, dank room in subterranean Manhattan was the site of a ghastly murder.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

Hear the tales of New York's most notorious criminals.

Discover the taste of mold.

An accidentally hidden library containing the ephemeral history of New York.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

Northern Ireland's Brobdingnagian stepping stones.

The atmospheric road was never meant to be so creepy.

The ruins of a once-grand mansion in Northern Ireland are now thought to be haunted.

This Italian-style temple replica has been threatening to fall off the Irish coast for hundreds of years.

Petrified footprints of one of the very first vertebrates to walk on land.

Just a few miles off the western coast of Ireland lies an isle steeped in Irish literary history.

This floating garden in the sky is straight out of a fairy tale, but the real thing is nothing short of magical.

A retired military stronghold on the rolling green coast of Donegal.