The Mason District mainly consists of a large flooded park surrounded by buildings, with a metro entrance in the south and north. Hubris Comics is at the northwest. In the flooded park, right outside Hubris Comics, are some super mutants with a captive.
Mason District can be reached through three underground tunnels:
- Falls Church/Mason Dst Metro from Falls Church.
- Through the flooded metro from the vicinity of Arlington Library. This is not recommended, unless you feel like fighting many mirelurks in an underground radioactive maze.
- Taking the Hubris Comics utility tunnel from the vicinity of Wilhelm's Wharf near Grayditch and Super-Duper Mart.
- Dean's Electronics, in the Pulowski Preservation shelter just outside Hubris Comics.
- Guns and Bullets, at the sniper's nest on the second floor of a building that overlooks the park (southwest corner).
- There is a sniper's nest that overlooks the park, in which the skeleton of a long deceased sniper can be found on the knocked over chair they were sitting on, and the rifle near the body. The corner apartment at the intersection of Jarndyce Way and Dexter Ave contains the nest on the second level.
- There is an inaccessible entrance to an unknown metro station in the eastern part of the map. This entrance contains two escalators, but they are fully blocked by debris.
Mason District appears only in Fallout 3.