Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

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

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

This ultra-modern California span is actually a titanic solar clock in disguise built by famed architect Santiago Calatrava.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

A huge musical instrument played by the ocean.

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

An extensive collection of ancient Egyptian artifacts and mummies.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

The world's first permanently occupied mountain-top observatory continues to report on the stars.

This controversial depiction of the "Founder of California" looks as though it was sculpted from mashed potatoes.

A 1920s speakeasy that had rum runners racing up and down the shores of California.

San Francisco's newly reopened hands-on science museum.

Floating man-made island and upscale restaurant.

A man-made island in scenic San Francisco Bay.

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

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.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

A living time capsule of the 1960s Richardson Bay water-front.

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

A 300-ship graveyard, with a few still visible at low tide.