This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

A geological mystery on Camelback Mountain.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The final resting place of soldiers' loyal canine companions.

A six-ton wedding present for the King of the Scots.

The only surviving prototype of Buckminster Fuller's revolutionary car.

One woman's Viking Castle on Lake Tahoe.

Despite being a perfectly pleasant place to be, Loyalton can't seem to attract any visitors.

A statue commemorating the heroic life of a Viking postman who was the Godfather of California skiing.

Bits and pieces from the ill-fated Donner Party's winter cabins.

Oh, just a motel on the edge of the desert decorated with thousands of clowns conveniently located next to an abandoned graveyard.

An elaborate shrine dedicated to the four corners of the world unfortunately misses its mark.

Home of the "true" equator.

Modeled after a famous church in Vienna, Austria—but in Helena, Montana.

The famous boat that once ferried Bogart and Hepburn still floats in Key Largo after being abandoned for years.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

The modern birthplace of Irish freedom.

This WWII plane died a quiet death, and is now a garden eel playground.

This Nevada lake holds its titular natural pyramid and, if the legends are true, a number of dangerous spirits.

These giant metal horses graze on a hilltop near the Montana highway.

The tomb of one of Scotland's bloody historic villains is a magnet for bumbling desecrators.