Concrete strongholds stand guard over the Golden Gate.

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

A huge musical instrument played by the ocean.

A formerly glacier-tipped volcano that inspired none other than Jules Verne.

Dozens of large, brightly-colored paintings adorn the walls of the "street art capital of Iceland."

A world-class theater sits hidden in this remote town in West Iceland.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This wrecked airplane has been sitting on a black sand beach since the 1970s.

The final resting place of the controversial chess champion.

This stunning concert hall has become a symbol of Iceland's national recovery.

Red frames showcase remnants of one of New York's original subway stations.

A small peaceful park and waterfall tucked amid the urban grind of Midtown Manhattan.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Tel Aviv's popular neighborhood went though endless waves of transformation.

This full-sized orange tree lives suspended in mid-air above the streets of Jaffa.

A throwback train ride transports passengers through one of the lesser-known national parks in the country.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

A toxic ghost town sitting atop a massive coal fire.

The site of a tragic massacre that spawned a multimedia franchise.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

There must be a pun in this haystack somewhere...

A creepy sculpture of a decapitated head invites viewers to see St. Louis through its empty eyes.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.