A true Pittsburgh institution that has inspired a nationwide chain, Primanti Bros. restaurants specialize in towering sandwiches made up of a half-pound of meat, cheese, tomatoes, crispy fries and sweet-and-sour coleslaw, all piled on crusty Italian bread and served on wax paper. Lore has it that the original Primanti's (in the Strip District at 18th Street) invented the sandwich as a one-handed meal for on-the-go truckers hauling produce to nearby markets. But then again, the owners simply may have run out of flatware and improvised by cramming a plateful of food between two pieces of bread. Either way, there's no denying the gut-level appeal of these gargantuan sandwiches. Try the double egg and cheese or the Pitts-Burgher Cheese Steak. Winner of an America's Classics James Beard Foundation award. Full bar. Open 24 hours. Hours vary by location.