commuting from Washington DC to Baltimore?

[chongran]

I am a foreigner to attend a conference in Washington DC, I hope to visit Johns Hopkins Hospital in Baltimore. Can you give me some suggestions to go to Baltimore from DC by public transportation? If there are shuttles, how much is the fee and how often between shuttles?

 

[sugarhead]

well because they are so far from each other I would rent a car if possible... Taking public transportation between the two will be very hard and costly