The construction site is located west of Bunker Hill, southeast of the Mass Chemical building. The location can be divided into three points of interest, including a small garage to the west, the unfinished building, and the warehouse to the north.
West of the construction site, in front of the chained door exiting the unfinished building basement, is the garage. It contains a ruined Pick-R-Up, a couple of wooden crates, and a weapons workbench.
This building consists of nine floors and a basement. There are three finished floors with a few rooms, and several unfinished levels. The seventh floor features a fallen green sign that connects to the nearby broken section of the freeway.
A machine gun turret is located just inside the main entrance. A weapons workbench is located on the fourth floor. A steamer trunk is located on the eighth floor. A precariously placed cooler sits on the end of one of the girders that comprise the ninth (top) floor. Dropping down the elevator shaft leads to the partially flooded basement containing a steamer trunk.
On the broken section of the overpass accessed from the seventh floor is a toppled trailer to the north with a locked trailer door (Master lock). This contains a Vault 81 steamer trunk. To the south is a construction lift that ascends to the top tier of the overpass, and another lift is further south (though there is nothing of value on the top tier). It is possible to jump to the next section of the road and continue past this lift to arrive above the garden terrace. At the end, it is possible to descend some stairs and continue over a walkway to a door into the Commonwealth Bank.
Construction site warehouse
To the north of the construction site is the warehouse. It has two doors, one leading to the construction site, the other to Charlestown. It houses a forklift mounted on caterpillar tracks. A sleeping bag can be accessed on the catwalk. A super mutant is usually guarding the building.
- Weathervane: Tinker Tom asks the Sole Survivor to placed atmospheric sensors on high vantage points to detect any anomalies in the air.
- While not directly associated with the quest, this location's heavy super mutant presence may cause difficulties while completing Boston After Dark.
- The utility Protectron in Mass Chemical, if activated, will proceed to the unfinished building and engage in combat with any super mutants it encounters.
- There may be super mutant suiciders on the ground level of the unfinished building, depending on the level of the player character.
The Cambridge construction site appears only in Fallout 4.