Originally Posted by CrazyOne
Yeah, most of the Amtraks stop there (if not all), but I don't think they're any more frequent. Significant change in cost, too, I belive about 3x as much.
Last I checked, a one-way Amtrak ticket from BWI to Washington Union Station was $13, and a one-way MARC ticket $6. So it's about twice as expensive to take Amtrak.
The B30 bus/Metro combo is even cheaper, but painfully slow (well over an hour from door to door).