Visiting D.C. and Maryland from LA. Looking for good old fashioned American comfort food like a good hot turkey sandwich, chili, club sandwiches, great burgers, and other artery clogging delights. Prefer to eat same in an old school (really old, not 50's recreation) retro restaurant with well worn interior. Anything from drug store lunch counter to an old clubby dark wood and red booth place. A local institution, iconic place would be great. Any suggestions much appreciated.