One of the most unusual geological features, recognizable from a dozen hit movies.

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

California's own medieval Italian castle, authentic down to the 300-year-old iron maiden in the dungeon.

Rainbow-hued local gem in Venice.

Most famous work of one of Frank Lloyd Wright's sons.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

The ghostly remains of an accidental sea.

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

A small Montana town commemorates the dog who waited at the train station every day for his owner to return.

This beautiful ancient site is dotted with perforated sandstone pillars considered sacred by some Native American groups.

These giant metal horses graze on a hilltop near the Montana highway.

A rapidly disappearing glacier filled with extinct grasshoppers, perfectly preserved in the ice.

This angular Dwarven tunnel cuts through a mountainside in Glacier National Park.

The rocks of a certain area of Butte, Montana give off a musical ring when hit.

Greenery cloaks this serene sculpture inspired by the famous Lost Gardens of Heligan.

On the Oregon coast there is a natural hole that seems to be draining the sea.

A home made entirely from scrapped, reclaimed and recycled material in Whitman County, Washington.

A volcanic fissure over two miles long and up to 70 feet deep.

Stroll through a wonderland of stupendous moss-covered trees.

An abandoned network of military bunkers and tunnels open for anyone willing to descend into the darkness.