Some of the best hikes in this region are in Canyon de Chelly, up the streambed between the soaring vermilion, orange, and white sandstone cliffs, with the remains of the ancient ancestral Puebloan communities frequently in view. Mummy Cave is especially worth a look, its three-story watchtower nearly perfectly preserved. The more weathered Antelope House and White House stand against the sweeping canyon cliffs as impressive reminders of a bygone era. The Navajo National Monument offers impressive hikes to two ruins: Beta-Takin, a settlement dating back to AD 1250, and Keet Seel, which dates back as far as AD 950. Both are in alcoves at the base of gigantic overhanging cliffs. Remember, you cannot hike or camp on private property or tribal land without a backcountry permit.