World's largest collection of serial killer artwork and other macabre exhibits.

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

An artsy hidden staircase leads to breathtaking views of San Francisco.

A psychedelic labyrinth on the San Francisco bay.

A huge musical instrument played by the ocean.

This "life-size" depiction of Mickey Mouse as a half-lobster is both whimsical and a bit creepy, standing guard over the Boston waterfront.

Millions of numbers carved in glass represent the tattoos forced upon victims.

A mysterious stone embedded at the base of a historic Boston building.

On a former island, this old fortification once used to protect the Boston Area and started Edgar Allan Poe in his military career.

From bench to vandalism to art, this silly prank seat was funny enough to become permanent.

This giant Boston statue of Mary is standing on a globe to show her power over the universe.

Ice cream stand, snack bar, and time capsule of milk conveyance.

The massive machine creates cracking displays of indoor lightning.

The often-overlooked ruins of one of the first buildings designed by famous landscape architect Frederick Olmsted.

Ralph Waldo Emerson spent two years living here decades before it became a Frederick Law Olmsted-designed park.

The Boston square dedicated to the dark poet who was born nearby.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

An enormous, inside-out glass globe built in 1935.

In the hometown of the Grand Ole Opry star is a larger-than-life memorial statue made entirely from chicken wire.

Mysterious library of an infamous financier and spiritual seeker.

Abandoned for 60 years, this submerged bridge was completely forgotten until the lake was drained.

An unknown Hall of Fame in Jackson, Tennessee.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.