Stroll through a wonderland of stupendous moss-covered trees.

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

A huge musical instrument played by the ocean.

Buy a token from the liquor store and you can make this beast spew flames on command.

A stealthy Apache hideaway that became the haunting site of a mass grave.

This lab's maddening silence is good for business but bad for sanity.

An acoustic anomaly with a mysterious cause.

America's most famous piece of self-built architecture.

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

Mile-long cave system near Great Smoky Mountains.