I have enjoyed eating at the Guard House, located in a very close-in suburb of Philadelphia.

http://www.guardhouseinn.com/docs/history.html

The food is very well prepared, and the old age of the building is confirmed by the very low ceilings and general lay-out. It also has a nice small bar (usually with what look like a few regulars as well as non-regulars), and a couple of smallish dining rooms.