From Reagan airport to Baltimore downtown
 

I am looking for fast transportation from Reagan airport to downtown Baltimore.

Cabs are quite expensive, but probably the quickest way if not during rush hour and there are no accidents. Unde good conditions it should atake about an hour by cab. Less expensive and possible just as fast depending up on the time of day, try the metro and train. At National (Reagan Airport) take the Yellow line toward Mt. Vernon Square to Gallery Place and change at Gallery Place to the Red Line towards Silver Spring. That should take about 25 minutes. the url for Metro is http://www.wmata.com/. Take Amtrak from Union Station to Penn Station in Baltimore which should take about 40 minutes. Amtrak's url is http://www.amtrak.com/servlet/Conten...mtrak/HomePage.
Depending upon the time of day driving will take over an hour.

Another option that takes just 15 minutes longer is to ride the MARC train from Union Station to Baltimore, and the fare will be a LOT lower.

Find schedules for PENN LINE at http://www.mtamaryland.com/schedules...c_schedule.cfm

MARC does not run weekends or most Federal Holidays.

oops- I neglected to say take the Metro red line to UNION Station where you transfer to Amtrak or the Marc as susggested.