BWI Rail Station is an intermodal passenger station in Linthicum, Maryland near Baltimore/Washington International Airport. It is served by Amtrak Northeast Corridor intercity trains, MARC Penn Line regional rail trains, and several local bus lines.
The station is located just over a mile from the airport's terminal. It was the first intercity rail station in the United States built to service an airport. A free shuttle bus runs between the station and the airport terminal at all hours.
Although Penn Station is the Baltimore area's main intercity station, BWI Airport is a major station in its own right.
Wikipedia https://en.wikipedia.org/wiki/BWI_Rail_Station
Coordinates 39°11'32.891" N -76°41'39.717" E