Meaning "bad land" in Spanish, the landscape here is formed mainly by lava flow.
An enormous collection of weirdly-shaped rock pinnacles, remnants of a huge volcanic eruption about 25 million years ago, cover the higher regions of the park.
Offering rugged hiking trails, it protects a wilderness area containing the remains of half of a long-extinct volcano.
In a remote and wild area in Southern Arizona, you can visit the largest concentration of organ pipe cactus.
Once inhabited by the ancient Puebloans, today a land of enigmatic ruins and superb canyon scenery.
It preserves the prehistoric ruins of an ancient Hohokam community.
The National Monument actually comprises three canyons, with walls rising steeply for about a thousand feet.
An extinct volcanic crater on the south coast of Oahu, measuring 1200 feet high.
An International Biosphere Reserve, a World Heritage Site, and a Wetland of International Importance.
A unique area in the Mexican Caribbean, with a natural landscape, rich flora and fauna and miles of pristine beaches.
