Old school and off the beaten path (aka NOT in the city of Baltimore), situated by BWI, G&M is consistently rated as having the best crab cakes in the region.  They are all meat. no filler and taste so damn good you’ll forgive the rather rough around the edges, non-hip, non-classy appearance of the place.  Perfect for a first or final meal in the area after/before your flight.  You will need a car, as G&M is not accessible by public transportation, to my knowledge.