I was there... parked on the grass beside the nearest gas station and walked the mile. When the rally ended, walking on the dark road with that many people was like a scene out of the walking dead, but instead of mumbling slouched zombies, it was briskly walking patriots rambling about Christ and conspiracies :)

There is less than 30 parking spots at the actual airport. Looked like about 25K people there this evening. I can tell you that area is dense woods. I grew up there.