More than 800,000 people visit Petrified Forest National Park every year to explore the Painted Desert or discover ancient fossil trees. Nationwide, the National Park System hosts over 285 million visitors per year. The 1916 NPS Organic Act mandates that parks be managed not only for the enjoyment of today's visitors, but 'preserved for future generations' as well. To achieve both, parks must be managed in a way that minimizes our collective footprint on the land. In a word, parks must be sustainable. Sustainability - Petrified Forest National Park (U.S. National Park Service)