When ecosystems collide in the arid Southwest.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

This naturally-sourced hot spring is now home to a clothing-optional resort.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

This painted marvel is San Francisco's 400-foot ode to urban biking.

Sitting atop San Francisco's tallest hill, a cross honors the victims of the Armenian genocide.

Once the site of speeding horses, now home to picnickers and public concerts.

A bronze tribute to a legendary Californian, the self-proclaimed "Emperor of the United States."

A former hardware store near Yerba Buena is the official home of California's history.

The original place where water met land in the City by the Bay is outlined in brass.

The first fresco Diego Rivera painted in the United States can be found in the former San Francisco Stock Exchange.

This tall and trim architectural oddity is one of the skinniest buildings in San Francisco.

Once the fastest ship from San Francisco to Tahiti, the Galilee now lays in pieces in three different cities.

This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

Noble beasts perhaps, but not the Emperor's dogs.

The sole surviving relic of the San Francisco neighborhood cobbled together from old horsecars and streetcars.

This Japanese treats shop may have been the first business to mass-produce fortune cookies in the United States.

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

Towering basalt columns, a creation of fire and ice.