Located in Glen Helen Regional Park, this is the largest outdoor amphitheater in the United States, with a capacity of over 65,000 in the seats and on the lawn combined. This extremely popular Southern California venue was sadly corporately renamed in the 1990's and again a few years ago and surely it'll be renamed again in the future.
Theatres - Amphitheatre
Links: www.livenation.com
By: AKpilotEMT
http://www.livenation.com/San-Manuel-Amphitheater-formerly-Glen-Helen-Pavilion-tickets-Devore/venue/73734
new current name: San Manuel Amphitheater (named after a band of Mission Indians or more specifically after their corporate Indian Bingo & Casino.)