Today marks the 50th anniversary of the Summer Jam. The largest crowd that ever gathered for a rock concert was at Watkins Glen, on July 28th 1973.
About 150,000 tickets were sold for the one-day festival, but an estimated 600,000 people turned out to hear the Grateful Dead, the Allman Brothers, and the Band.
Each of the three groups at Watkins Glen played unusually long sets. The Grateful Dead performed for five hours, the Allman Brothers for four, and the Band for three, including a thirty-minute break due to a thunderstorm.