BWI Marshall Airport offers several free, high-frequency courtesy shuttles to get you to and from various destinations around the airport campus.
The Parking Shuttle, which runs between the airport terminal and the Long-Term A and B lots and the Daily Garage, operates on an approximate 8-10 minute frequency.
The Amtrak/MARC Shuttle operates between the airport terminal and the Amtrak/MARC Station on an approximate 10-minute frequency*.
The Rental Car Shuttle, which runs between the airport terminal and the Consolidated Rental Car Facility, operates on an approximate 8-10 minute frequency*.
*During late night and early morning hours (1am-5am), Amtrak/MARC and Rental Car shuttles operate on an approximate 25-minute frequency.