The check point broadcasts an old world military beacon emergency frequency RJ1138, calling all South Boston Army soldiers to its coordinates.
As of 2287, the checkpoint has fallen under Gunners control, with an unnamed Gunner commander in charge of it.
The check point is located directly west of the Castle and past the bridge just outside of the South Boston area. It consists of two structures, the main building guarded by two Gunners and a trailer where a single Gunner is often found resting. There are also various car wrecks in the area.
In the main building there is a Master-locked safe with plenty of ammo as well as several other containers. Two beds and a weapons workbench are also available in this building. On the western side of the building, there is a cage that can be opened with a nearby Expert-locked terminal. The cage contains a power armor station, a full set of power armor and a Mini Nuke.
- Guns and Bullets issue #7 - On a desk within the checkpoint building.
- Fat Man - Found inside the trailer.
- Leveled power armor - Inside the locked cage just outside the checkpoint building. Opening the cage requires to hack the nearby Expert-locked terminal.
- One Mini nuke - Inside the locked cage behind the power armor.
- Two fusion cores - One near the elevator to the highway, the other is pre-installed in the power armor suit.
- Sleepwalker's note - East of the South Boston military checkpoint, on top of an overpass accessible by a lift. The note is inside a camper.
- Learning Curve - This is one of the locations the Sole Survivor can escort a scribe of the Brotherhood to.
- Quartermastery - Recover tech for Scribe Haylen.
- Randolph Safehouse
- The power armor frame here yields a full suit of leveled power armor that maxes out at X-01 Mk I at level 28, quite in contrast to other full X-01 sets that reach a maximum tier of Mk III at level 47.
- The items (including the Fat Man) respawn faster than the Gunners do.
- Several companions have quotes when entering the checkpoint area:
- Nick states that the repeating message was there "as long as [he] knows," and that "This must be the reason everyone's crazy inside."
- Hancock states with a level of stress in his voice, that "There must be a way to turn it off!"
- Cait and Preston Garvey similarly mention a need to turn off the transmitter.
- Piper sarcastically says "Ugh! Yes! We hear you." as the transmitter repeats.
The South Boston military checkpoint only appears in Fallout 4.