With some infrastructure upgrades, they could merge the VRE and MARC routes to have regional rail that runs through DC between Maryland and Virginia. Crystal Ci

With some infrastructure upgrades, they could merge the VRE and MARC routes to have regional rail that runs through DC between Maryland and Virginia. Crystal City already has a VRE station, so this could enable relatively painless commutes from as far away as Manassas, Fredericksburg, Rockville, and even Baltimore. However, there are major organizational and political hurdles that would have to be tackled to put any new infrastructure to effective use, so I wouldn't hold my breath. But maybe Amazon's choice of location could spur things in the right direction.