Farouk El-Baz
Farouk El-Baz, a Boston University research professor and expert on crowd estimation, told the "LA Times" that his informal research from media coverage indicated 75,000 as the peak attendance. El-Baz noted that, because there seemed to be no aerial photos of the event, reaching any sort of rigorous estimate might be impossible. The Washington Metro reported 87,000 extra riders that day as compared to the average ridership.