I’ve been analyzing filled stadium photos to get an idea of what a crowd of about 60K looks like. IN doing that, and looking at satellite images of Obama’s inauguration, I think HIS numbers were around 1 million and not more than that.
I think today’s crowd was 500K at the march, which is still very impressive. If you include latecomers, well, maybe 550K
It's a shame we didn't think ahead to get somebody to take a photo from the top of the Washington Monument.