This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

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

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

See massive fossils that are over 200 million years old in northeastern Arizona.

Final resting place of Geronimo, Quanah Parker, and the first atomic gun ever fired.

The humble beginnings of the man known for his lavish "champagne" music.

The center of the only hemisphere that awards visitors with a commemorative coin.

The humble Hoosier roots of a famed Broadway composer.

The evolution of recreational vehicles and motorhomes is on display in the “RV capital of the world."

A singular collection of hand-built art deco cars are held in a building with style to match.