A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

California's own majestic geyser is powered by a subterranean volcano.

This Seattle museum displays the history of the telephone through an impressive collection of telecom equipment.

This semi-secret garden in south Seattle emulates a traditional Japanese garden using the plants of the Pacific Northwest.

This lovely hilltop tower was specifically built to withstand 100 MPH winds.

These black pillars of volcanic basalt seem to call mountain climbers with an unbreakable siren song.

The library of every book lover's dreams.

Hikers can still stroll beneath the long conveyer of this abandoned mining facility hidden in a West Virginia river gorge.

This Detroit ruin was once a gothic bastion of its community, but now it stands as a haunting ruin.

A crumbling stone stable and carriage house are all that remain of a manse that was once filled with Egyptian artifacts.

This naturally heated mountainous creek has created a group of neon blue pools of potentially deadly boiling water.

Tour the luxe "glass cage" that inspired and unnerved the architecture world upon its debut.

One of the only Florida forts to remain in the hands of the Union all through the Civil War still stands as a historic stronghold.

This Pennsylvania cave holds evidence of the oldest known inhabitants of North America.

The lush coastal city of Astoria is riddled with forgotten secret sidewalks.

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

Celebrate the history of the rich and truly misunderstood relationship between man and pigeon.

This historic cliffside mansion uses a natural cave for air conditioning.

The largest man-made crater in the U.S. marks the spot where we once tested mining with nukes.

This humble star-gazing center touts itself as the "Birthplace of American Astronomy."

This odd California folly seems like it was almost designed to accumulate urban legends.

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

Cave where bat-eating snakes hang down from the ceiling.