A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

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

The famous aviator's final resting place is a study in natural beauty.

A unique set of caves that spits waves back out into the ocean.

Climbing this abandoned railway leads to breathtaking vistas of O‘ahu.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

Guns that have been defending San Francisco since 1904.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Its buzzing collection honors vibrator history.

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

Visible below the waves are memorials to the city's Gold Rush dead.

This residential door allows San Francisco muggles a glimpse at the wizarding world.

Built in 1906, this unique building was the first Hindu temple in the United States.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.