How much should you pay for a great hamburger?“The best ones fall between $10 and $20,” says burger enthusiast Keith Flanagan, who’s also an account executive at a New York City public relations firm. “Anything less should make a foodie question the quality, and anything more should make a foodie question the restaurant’s hubris.”Once the ultimate cheap comfort food, the burger is increasingly becoming a gourmet indulgence—often prepared with grass-fed, Kobe-style beef, topped with shaved truffles, or rendered quirky through toppings such as fried duck eggs. So where to go to sample the best burgers? Providence, RI, according to T+L readers, who voted in the annual America’s Favorite Cities survey to rank cities on features that delight travelers, among them, irresistible foods like pizza and burgers To be fair, the survey’s list of 35 major metropolitan areas didn’t include some smaller towns that were key in the burger’s evolution, such as New Haven, CT, home of the legendary Louis’ Lunch, or Wichita, KS, where White Castle sold the first burger that resembles what Americans eat today.Other cities in the top 20, however, have their own claim on hamburger history. The Los Angeles area launched the first McDonald’s and the In-N-Out Burger, both in the 1940s. Minneapolis/St. Paul, meanwhile, is famous for the Juicy Lucy, a burger with the cheese cooked inside the patty.While some cities keep it simple (Dick’s Drive-In in Seattle serves an old-school $1.50 burger), others like Philadelphia’s Hickory Lane American Bistro aim higher. “It’s not just a sandwich anymore—it’s become an entrée,” says owner and executive chef Matt Zagorski, whose burger ($14) blends filet mignon, short ribs, and brisket.The No. 1 burger city, Providence, may have it both ways, offering both classic and creative burgers, with an emphasis on locally sourced ingredients—within reason. At Harry’s Bar and Burger, you can wash down your 100-percent-Hereford-beef sliders with spiked milkshakes, such as the Caramel Twinkie, made with ice cream, vanilla vodka, and snack cakes.Purists like chef Zagorski think that the power of a great burger meal ultimately comes down to the high-quality beef. Why not just eat a good steak then? “Because,” he says, “it would be sacrilege to put cheese and mayo on a steak.”