Big general admission area on the floor where you can dance, surrounded by stackable bleachers that go up 12 feet. Then there is the regular bleacher seating for whatever event. Holds maybe 6000. The sound was loud & clear in this place. I remmeber Phil's bass in my chest!
Missoula is a far west hippie friendly town, unlike some other Montana college towns (Bozeman). It's definitely worth a look around the town and the Blackfoot for a float or fishing.