Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

This single room has survived the centuries with almost no deterioration.

Ireland's most remarkable collection of these curious cone-shaped houses is worth the buzz.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

These unusual rooms on wheels are holdovers from the 1960s.

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

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

A collection of 20th-century automata, penny arcade games, and musical contraptions.

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

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

Once the largest windmill outside of Holland, with enormous 114 foot sails.

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

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

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

Swarms of butterflies cannot compare to the awe inspired by the publicly-funded nakedness once displayed in this sunken garden.

Built for an exposition in 1915, these horticultural displays have stood the test of time.

North America's largest accredited model railroad museum.

Tijuana's legendary jai alai or "basque ball" palace is now a massive music venue.

One of the largest trees of its kind in California.

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

A burnt orange monolithic dome structure perched on a hillside near Interstate 280.

A gathering of green robots at the Googleplex.

The garage at the childhood home of Steve Jobs was a hangout for the founders of Apple, even if they never built computers there.

A giant chess set, minus the psychedelic drug trip.