America's first national park was established in 1872. Home to an abundance of wildlife, from grizzly bears and wolves to bison and elk, Yellowstone covers areas of Wyoming, Montana and Idaho. With no public transportation, traffic is congested in summer. Most visitors come for Old Faithful and the other extraordinary geysers and hot springs, but the Grand Canyon of Yellowstone, Gardner River Canyon and Boiling River are other stunning sights. Hiking, biking, boating and ranger-led tours add to the fun.