By Light Rail
The MARC trains provide a light rail service between D.C. and the Delaware border, passing through the same stations as Amtrak, but with a few more stops, and lower passenger fares.
By car
The big highway running north-south is I-95, which runs up from D.C., past BWI, through Baltimore, and then up the coast through all the major East Coast cities.
Other important routes include I-70, which goes into Baltimore from Western Maryland; I-83, which runs north from Baltimore to York, Pennsylvania; I-97 between Baltimore and Annapolis; and US-50, connecting Annapolis to D.C.
By train
Amtrak is the major operator on the East Coast, and the Northeast Corridor, which runs between D.C. and New York, crosses the region, with notable stops from south to north at New Carrolton, BWI Airport, Baltimore, and Aberdeen.
By plane
Baltimore-Washington International Airport BWI is a major point of entry to the region, with the Southwest Airlines hub providing a lot of cheap flights from all over the country.