Here is a picture of the game between the San Francisco 49ers and Dallas Cowboys. It is a home game for the Dallas Cowboys:

Niners fans are loud as hell at Jerry World pic.twitter.com/eq5pItObWD — Luke Zimmermann (@lukezim) September 7, 2014

Yeah, that's AT&T Stadium. Of course, there are always traveling fans at road games, but this seems like a whole bunch, especially considering the Cowboys tend to have, you know, fans. (The game isn't going too well for the Cowboys either, as they're down 21-3.)