For commuters in Northern Virginia, there are several different options of transportation available. People who work in Washington or surrounding areas can choose between different bus lines, Metro, Virginia Railway Express, or they may choose to carpool or Slug.
Slug lines are often located along commuter bus routes or near Metro stations, as the bus or Metro can serve as an alternative when Slug rides are scarce. In order to get to certain Slug or bus lines, sometimes commuters may have to ride a couple of stops on Metro, of which I am not a huge fan.