Estimates of attendance for the march vary widely. The Philadelphia police gave no official estimates, but were preparing for up to 600,000 people. However, a study provided by the University of Pennsylvania that made use of aerial footage, photos, and other research data and information obtained from news and other sources, indicates that the gathering drew at least 500,000 people. Police sources gave numbers varying from 300,000 to 1 million. The attendees came despite cold temperatures and light rain.
