The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

When ecosystems collide in the arid Southwest.

A statue high in a hill that represents how Buffalo Bill got his name.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

An experimental, automotive replica of Stonehenge.

A stealthy Apache hideaway that became the haunting site of a mass grave.