Formerly manned by soldiers from Echo Company of the 104th Infantry Regiment, the checkpoint was responsible for searching vehicles for contraband, and was authorized to disassemble vehicles to this end. When the Great War broke out, the checkpoint began broadcasting on emergency frequency RJ1138, calling all South Boston Army soldiers to its coordinates in a loop. As of 2287, the checkpoint has fallen under Gunners control, with an unnamed Gunner commander in charge.[Non-canon 1]
The checkpoint is located directly west of the Castle and past the bridge just outside 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. The trailer houses a sleeping bag and a mattress, as well as a Fat Man.
In the main building, there is a Master-locked safe with ammunition and other containers with minor loot. Two beds and a weapons workbench are also available in this building. On the northern side of the building lies an APC. On the western side of the building 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. On top of the building lies a skeleton next to a leveled combat sniper rifle.
- Fat Man - Inside the trailer.
- Guns and Bullets issue #7 - Inside the checkpoint building, on a desk.
- Leveled power armor - Inside the locked cage just outside the checkpoint building.
- One mini nuke - Inside the locked cage behind the power armor.
- Two fusion cores - One is installed in the power armor suit, and the other is near the elevator to the highway to the east.
- Chinese stealth armor - In a trunk.
- Cleansing the Commonwealth: Knight Rhys gives the Sole Survivor an assignment to clear the location of what he calls "abominations" to further the aims of the Brotherhood of Steel.
- Learning Curve: After speaking with Proctor Quinlan, the Sole Survivor can agree to escort a Brotherhood scribe on a research patrol. They will travel together to acquire data and return it to the Prydwen to further the Brotherhood's aims.
- Quartermastery: Scribe Haylen has identified the location of a piece of technology she wishes to retrieve and catalog. She asks the Sole Survivor for help in bringing back the technology in one piece.
- Randolph Safehouse: The Railroad agent Mister Tims will leave dead drops in the form of six holotapes for the Sole Survivor, containing information about possible hazards to the Railroad's escort and escape of synths out of the Commonwealth. They can assist in these efforts by clearing out the location of hostiles.
- A Permanent Solution: One of the leaders of the Nuka-World raider gangs tasks the player character with neutralizing a target to further their gang's aims.
- Burned on the River
- Can You See Me Now?
- The power armor frame here yields a full suit of leveled power armor that maxes out at X-01 Mk I at level 28, 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.
- When at this location, companions make comments.[clarification needed]
The South Boston military checkpoint only appears in Fallout 4.
- Fallout 4 Vault Dweller's Survival Guide Collector's Edition p.373: "[6.10] SOUTH BOSTON MILITARY CHECKPOINT
Just west of South Boston Neighborhood, this was once a gathering place for military but is now an ambush spot for Gunners. There’s a Fat Man inside the truck trailer, loot (including a magazine) inside the small bunker, and a wall safe (Master). Unlock the outside terminal (Expert) around the back to access a small secured area with Power Armor and a Mini Nuke."
(Fallout 4 Vault Dweller's Survival Guide Map)