This collection of historical artifacts and tropical wildlife waits just beneath the surface of the water.

A free, public museum dedicated to the fascinating science of sight.

The grand, column-fronted, sculpture-adorned home of the ambitious digital library.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

A psychedelic labyrinth on the San Francisco bay.

One of the last Jazz Age "Wonder Theaters" in New York City.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

A masterpiece of LGBT art has been restored in what may now be the most valuable restroom in America.

Just your average Marie Antoinette–themed speakeasy in an abandoned 19th-century subway tunnel.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

First LEED-certified gas station in the United States.

This symbol of peace is appropriately positioned overlooking the Pacific Ocean.

This grand mansion has starred in everything from Bones to Buffy.

Fall down the rabbit hole into a surreal journey of human consciousness "from ass to soul."

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

This spooky road cut through a mound of ancient coral might be haunted by a witch.

This beautiful Miami garden was designed as a laboratory for tropical plants.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

Japanese gardens dedicated to the Japanese farmer that refused to throw in the trowel.