These black pillars of volcanic basalt seem to call mountain climbers with an unbreakable siren song.

Home to the deepest rift anywhere on Earth.

These elusive, isolated rodents evolved into a distinct, locally iconic subspecies.

A monument to the one-armed geologist who led the first documented expeditions through the Grand Canyon.

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

Limestone caves with spectacular showcase chambers.

A sharp bend in a dramatic river canyon cut through red rocks.

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

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

2300-year-old Roman road connecting the empire.

Despite its name, this route in southern Utah offers a heavenly day trip.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

A secret climbing tree hides along the side of a Costa Rican road.

This Costa Rican chapel is the most metal church in the world, literally.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.