The public has spoken: America's national parks are crowded. Consumer Reports asked 40,000 of its subscribers to rate their experiences in America's national parks. The survey found that along with spectacular scenery, Yellowstone and the Grand Canyon offered headaches over parking, bad roads and too many people. Yellowstone, the nation's first national park, ranked 27th on the list of visitor satisfaction. The Grand Canyon also did poorly, ranking 22nd. Maureen Oltrogge, Grand Canyon National Park spokeswoman, says that overcrowding is an old complaint. During the park's peak season, an average of 6,500 cars a day compete for 2,400 parking spaces. Says Oltrogge, "Planners never imagined that so many people would use the national parks." Alaska's Glacier Bay National Park was rated highest for overall experience followed by Utah's Arches, Carlsbad Caverns in New Mexico and Utah's Canyonlands. For the full survey, see the June issue of Consumer Reports.