This remarkably simple jail went over a century without an escape.

A tree grown from astronaut seeds which were exposed to cosmic rays.

This municipal playground was co-created by the father of one of the most playful characters ever.

The longest burning light bulb in the world.

This giant shopping mall still holds signs of its automotive past.

A life-sized mammoth sculpture marks the spot where the remains of a Columbian mammoth were discovered in 2005.

A statue commemorate Tommie Smith and John Carlos's brave protest at the 1968 Olympics, a watershed moment for civil rights.

The headquarters of a secretive order is also a beautifully-designed park.

The largest permanent Monopoly board makes one of the longest games even bigger.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

Of all the origin stories for weed's secret code, this one likely has the goods.

Over 315,000 preserved amphibians and reptiles in jars.

The stones that traveled from Spain to eventually become a holy place for San Francisco's nature worshippers.

This mountaintop beacon is only lit three times a year but shines like some kind of all-seeing eye.

Spiral labyrinth hidden in the hills above Oakland, CA.

This museum boasts the ninth-largest collection of insects in North America.

An extensive collection of ancient Egyptian artifacts and mummies.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A tribute to the life and work of the beloved "Peanuts" cartoonist.

This abandoned boat was left in place thanks to its rotting beauty.

'Cause the fence start shaking, the earth was quaking.

A raised boardwalk winds through a thicket of stunted, century-old trees no more than nine feet tall.