No one can really beat Ray's in the DC metro area. The burgers here are just that darn good, and everyone knows it. Even folks living in the District (like myself) make trips just to get some Hell Burger. It's not big, it's very unassuming, and if you don't know where you're going you can easily miss it. But when you're there, the vibe is bustling and the options are great - Ray's has many of their own versions of a regular hamburger, but you can get a classic one if you want. I'm a fan of The Mack, which is pretty close to a classic burger but with Ray's special sauce; the Let's Get it On is amazingly greasy with its sauteed vegetables. There is no hostess and you just sit wherever you can once you get your burger, but I've never waited more than 5 minutes for a table so it's never a problem.
Pros: huge, burgers; perfectly cooked meat; unique fixings
Cons: may have to wait for table
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