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

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

The biggest solar telescope in the world helps reveal the secrets of our sun.

A reproduction of earth's many biomes.

An amazing collection of model trains, collectibles, and artifacts that span the last 100 years.

A natural history wunderkammer in the middle of the desert.

Hike the unusual hoodoos and rock formations that form this little-known natural wonder.

A rare wayfinding portmanteau of “Street” and “Avenue.”

This iconic 1958 tower welcomes air travelers to Tucson with neon-lit letters and architectural style.

After a short-lived attempt to bring America in line with the rest of the world, this road was left in metric.

Legend says train robbers stashed their gold within the depths of this unusual cave.

Collection of vintage trailers double as hotel rooms.

A living snapshot of a different time in America is preserved and maintained by a community of volunteers.

Stairs often replace streets on the steep slopes of this old mining town.

Limestone caves with spectacular showcase chambers.

The Jewish section of the famous Boothill Graveyard was abandoned for nearly 100 years.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

An old saloon in the West filled with history, and according to some, a few dozen ghosts.