Enjoy a tour into the canyon by vehicle, horseback or hiking. Most park visitors arrive by automobile and view Canyon de Chelly from the rim, following both North Rim Drive and South Rim Drive. Ancient ruins and geologic structures are visible, but in the distance, from turnoffs on each of these routes. Deep within the park is Mummy Cave. It features structures that have been built at various times in history. Private Navajo-owned companies offer tours of the canyon floor by horseback, hiking or 4-wheel drive vehicle. There is no entrance fee to enter the park, apart from any charges imposed by tour companies. Canyon de Chelly National Monument was authorized in 1931 by President Herbert Hoover in large measure to preserve the important archeological resources that span more than 4,000 years of human occupation. The monument encompasses approximately 84,000 acres of lands located entirely on the Navajo Nation with roughly 40 families residing within the park boundaries.