where in maryland? if youre in the baltimore/washington metro area there are many many places - the 2 cities are only about 40 minutes apart from one another and are both easily accessible by car or train
in the dc area you have the nations capital with enough monuments and other historical sites to take up a years worth of sight seeing and exploration
in the baltimore area you have excellent theater and several good museums - the entire area around the maryland institute college of art is loaded with many artistic venues that attract a wide variety of visitors
both cities are historically significant so im sure youll find plenty to keep yourself busy
Chesapeake Bay, especially the area around St. Michael's is really cool, and has crab like there's no end. Some pretty neat ferries there, too. Take in the very western part of MD, too; some really pretty country.