This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

Most-visited and most-photographed slot canyon in the American Southwest.

Dramatic river bend surrounds a natural red-rocked pedestal.

These huge stone ovens in the desert fueled the Nevada silver boom, and may have also been a hideout for outlaws.

Metal water storage tank turned ethereal concert hall.

The longest living non-clonal organisms on Earth.

A Mars simulation in the southern Utah desert.

A whimsical, punny collection of "fence art" outside the tiny mountain town of Baker, Nevada.

This UFO landing strip was created by a charitable Wyoming city that was worried about residents of Jupiter.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

A sculpture for the sun and stars, created by Nancy Holt.

This plaque marks the site where the penultimate chapter in the journey of two doomed boys unfolded in an imagined parallel universe.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.

A shady solar power system that couldn't hold up to the harsh desert conditions.

Dig for your own trilobites in this goldmine of invertebrates.

The highest peak in Utah is the hardest to reach, but only if explorers choose the hard way.

An earthwork sculpture built by Robert Smithson in the Great Salt Lake only reemerges during drought.

Jurassic Park—A Still Life.

An absolutely beautiful 200-foot stained glass installation traces the evolution of knowledge.

This granite monument at the site of an ill-conceived tourist attraction is built from the same stone as the Mormon Temple.

Here lies Lilly E. Gray, an alleged "victim of the beast," but the reason long remained a mystery.

Largest collection of mounted dinosaur specimens in the world.

A replica that won't float away.