This hobbit-y little hot spring may be the oldest spring used by humans in all of Iceland.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This Chinese-style quartz sundial was saved in its final hour.

This sidewalk tribute honors Colorado's great culinary creation.

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

A collection of over 15,000 zines works to preserve DIY publishing culture.

Where scientists keep miles of very valuable ice from Antarctica and Greenland from melting.

A technicolor place of worship for Elevationists.

A stark reminder of the huge nuclear weapons plant that once stood on the site and its effect on the surrounding area.

A research lab and hands-on museum where visitors can experiment with retro technology.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

The clock that sets them all.

Alleyway plaque commemorating the death of a fictional character in The Maltese Falcon, not far from the author's home.

Fonts are born and bred here at the oldest letterpress type foundry in the United States.

Russian history in San Francisco.

The remains of a 12th-century chapter house in Golden Gate Park.

A man-made island in scenic San Francisco Bay.

Art from the latest counter-culture; kids who dye their hair blue and believe the future will be a post-apocalyptic water world.

A walk down memory lane in the heart of one of San Francisco's most notorious neighborhoods.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.