I was at a Phish concert once (I’m not a fan, just had a free ticket) — and they said there were 75K-80K people there. This is what it looked like from the air:

Image: Phish-pbi07.jpg

Image: phish.gif
Image: went-783950.jpg

I remember that was a ton of people. I have no idea what the final number was in DC, but I’d like to see some proper aerial photos.