A working model of the entire San Francisco Bay and much of the Sacramento River Delta, complete with regular tides that change every 14 minutes.

Internationally-recognized arts center housed in a century-old former military barracks.

Concrete strongholds stand guard over the Golden Gate.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

The unusual burial monument of Arizona's first governor.

Sleep where gangsters fell amidst smoke and flame, with nary a bullethole to show for the legendary struggle.

A cabinet of curious mathematical models and old calculators.

The cinder cone volcano with a less than complimentary name.

The highest point in Arizona is an oddly snow-topped peak within the otherwise arid state.

In Tucson a giant metal snake helps pedestrians cross a busy highway.

This southwestern historic site was designed and built by an artist who wanted his work to "feel at home."

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

This historic national park is covered in the stunning ruins of red rock pueblos.

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

The artist James Turrell is repurposing an extinct volcano crater as an observatory to experience the cosmos.

See massive fossils that are over 200 million years old in northeastern Arizona.

Eons ago, a rushing lava river formed this pristine passage through solid rock.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A self-built castle made by a mysterious man.

A geological mystery on Camelback Mountain.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

A sharp bend in a dramatic river canyon cut through red rocks.

A shining, cold, black organ lies in San Francisco's financial district.