One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Two thousand artifacts from around the world collected by one woman who loved to travel.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Visit a surreal landscape so otherworldly NASA actually used it to train the Apollo 17 crew.

This stream-carved gorge has inspired poets, hidden smugglers, and trained soldiers, all without losing its beauty.

"All Mountains - All The Time."

A contemporary art installation housed within a Gothic cathedral.

An ancient church on a tiny island covered in stone bible stories has controversially been turned into a museum.

A remarkably intact castle that once was the largest in Ireland.

Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

A four story, football field-sized, nine-grotto creation made of shells, minerals, and rare stones.

16,500-acre ranch filled with American heritage, geological wonders, and a giant pile of tires is the crown jewel of an intriguing tug-of-war.

This cemetery served as the only official burial grounds in Cambridge for nearly 200 years.

A small, but award-winning beach known for its literally spotless reputation.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

The largest source of fossilized insects anywhere.

See six states, pickled freaks, rocks, and antiques.

Famed architect Antoni Gaudi built this generous thank you gift to a friendly host who housed him during a job.

The largest self-built castle in the U.S., six decades in the making.

A huge cathedral single-handedly constructed by one eccentric monk.

Mass Grave of 48 colonists killed in a raid by Native Americans and the French in 1704.