St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

One of the U.S. Forest Service's only mansions is outfitted with a dinner table for floating food.

A circle of giant painted vases in the former pottery capital of the United States.

The inventor of a number of hybrid corn species is immortalized with a field of giant corn.

Once adorning a New York skyscraper, these reclaimed ruins now haunt an Indiana park.

Fresh wooden posts have been added to ancient holes to recreate a primitive henge clock.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

One of few surviving standpipe water towers in the U.S.

Entombed in this strange, white stone hill are the deadly remains of radioactive weapons production.

The iconic remains of the original Academic Hall that burned down in 1892.

This historic cliffside mansion uses a natural cave for air conditioning.

This massive home was constructed by one of the greatest conservationists in Colorado history.

This once-popular otherworldly landscape was formed by one of the largest volcanic eruptions in history.

Climb to the top of this spiritual tower, and you'll be rewarded with spectacular views.

This grand stone tower was dedicated to a famed American humorist almost by coincidence.

A downtown park built on top of unclaimed graves.

When ecosystems collide in the arid Southwest.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

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

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

Forever immortalized in concrete, this Simpsons etching was crafted by show creator Matt Groening.

A Roman-style column in Oregon hides a spiral staircase inside.

While it is not equipped to peer into outer space this observatory looks like it was built on the moon.