One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

Small Nevada town embraced its designation as the "Armpit of America" with an Old Spice-sponsored festival.

A beautiful geyser under environmental threat.

An architect's childhood fantasy treehouse made real.

Jail from the 19th century that was built by inmates.

Home to the deepest rift anywhere on Earth.

Visitors to this library are in for a real-world education in modernist architecture.

Largest man-made excavation on earth!

An earthwork sculpture built by Robert Smithson in the Great Salt Lake only reemerges during drought.

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.

Concrete strongholds stand guard over the Golden Gate.

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

An enormous illuminated figure dances on the Las Vegas strip.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

A man-made island in scenic San Francisco Bay.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

From the Difference Engine to the Cray-1, all under one roof.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

A still functioning vaudeville carousel that has operated for over a century boasts a colorful menagerie and past.

Impossibly life-like natural history models created out of glass by a father and son.

360-degree virtual reality chamber physically immerses scientists into their data.

Rodin's famous depiction of Dante's 'Inferno', amidst a sculpture garden of many of his other works.

Guarded by the Angel of Grief, the Stanford family tomb attracts an odd mix of halloween revelry and somber contemplation.