Thank you Ahmedzuhdi great help! ;-)
The only way to go thier with public trans. If you welling to spend 2 to 3 hours you can do that by using following directions. First get uber to the Reston metro station . Just 7 miles from dulles or so . Then head to DC union station you have to change to the red line when achive dc or you can check the merto guidance to get the right direction Then from Union station use the 8$ train to baltimore Thats the only way it will cost half price of uber or cab direct to Balitmore but make sure you did have time and patience to spend in this long planned trip it will cost between 25$to 35$ Good luck
If you put the airport and your destination into Google Maps, it will give you options on using buses and/or metro.
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