A local institution in a neighborhood that looks more and more like a mall every year, Mr. Bartley's Gourmet Burgers in Harvard Square serves some of the city's best burgers in a raucous, no-frills atmosphere. For more than 40 years, locals, students, tourists and professors have been squeezing into this cramped Massachusetts Avenue eatery for killer burgers, fries and onion rings, as well as milkshakes and raspberry-lime rickeys. A cash-only, no-booze, no-bathroom operation, the best way to experience Bartley's is to take the train rather than look for parking in this part of Harvard Square. If you're visiting on a weekend, prepare to wait in line and sit elbow to elbow with strangers at a communal table. Or plan a late lunch. Either way, prepare to order from a list of seven- or 14-ounce burgers named for local and national political figures and celebrities – the Donald Rumsfeld and the Condoleezza Rice were recent offerings – and forget about your cholesterol intake for the day. No alcohol available. Cash only. Serving lunch and dinner Mon–Sat. Closed Sun. Voted Best Burgers in the 2008 Boston magazine readers poll.