A modest reminder of treacherous waters at the Golden Gate.

Golden Gate Park's historic collection of plants.

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

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

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

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

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

A "Texanic" (gigantic Texas) collection of Art Deco architecture at Dallas' historic Fair Park.

A whimsical cottage from the 1300s with a preserved Victorian-era post office inside.

A fantastic castle rumored to be the birthplace of King Arthur.

Part museum, part piece of Arthurian-inspired history, this stately hall attracts King Arthur fans from miles away.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

The largest greenhouse in the world is home to over one million types of plants.

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

This Victorian-era public house has set the standard for pub-style elegance for over a hundred years.

A museum marks and documents the site of the Titanic's launch.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

This one has sailed five times as far as Sir Francis Drake's famous ship.

A naturally mummified 2,000-year-old man.

Scattered throughout London are ancient remnants of the city's former bounding wall.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

The "Prussian Versailles" that is as glorious today as when it was built.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

Metro station with a claim to rock n' roll fame.