Once the site of speeding horses, now home to picnickers and public concerts.

Art in the form of a winding, man made crack in stone.

A masterpiece in Golden Gate Park by virtue of the artist’s debt.

The legendary statue-hating superintendent of Golden Gate Park is honored with... a statue.

A man-made island in scenic San Francisco Bay.

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

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

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

Nuclear waste dump site now an environmental sanctuary.

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.

The fossilized remains of ancient California redwoods.

Death rituals and sacrifice inside a Peruvian megalith.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Granting the right of way to ships over surface traffic since 1917.

A giant Troll lurks under one of Seattle's oldest bridges.

A wall of chewing gum moonlights as collective art.

A walk through the historic city center, under the streets of Seattle.

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

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

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