The day after July 4 was hot and sunny and attracted so many people to Acadia National Park that it set a single day record for visits – and overwhelmed park staff with rescues of injured hikers and shutdowns of Cadillac summit and other areas because of heavy traffic. Among those rescued: A woman who suffered a heat stroke on Dorr South Ridge Trail and had to be airlifted by helicopter, and a man hiking down Cadillac West Face Trail who slid 40 feet and fell off a 15- to 20-foot cliff.