The Linebacker Lounge, Between the Buns sports bar, and Main Street Pub are all right there by campus on South bend Ave. If you want Italian there is Parisi's on South Bend Ave. and a Granite City Brewery (chain micro) at University Park Mall. Also, Belmont Beverage, right next to The Linebacker Lounge has a pretty decent micro selection too.
I would grab some beer and a cooler with wheels and cruise the parking lots. Wouldn't be a bad idea to pack some food too and extra beer. You'll have plenty of opportunity to swap beers and food with other tailgaters.
Given the size of South Bend it's surprising but it is not what I would call a beer town. For the most part the overall selection is not very good.
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