The big rally in DC filled a 1/3 by 1/4 mile rectangle. I think there was about 1 person per square yard, if you average out the crowd density.
That's 250,000 people. I'd like comments from others who counted sample regions in the crowd, etc, to get a more accurate estimate.
THE REV. MARTIN Luther King Jr. understood the meaning of discrimination and oppression. He sought ways to achieve liberation and peace, and he thus understood that a special relationship exists between African Americans and American Jews.