According to a holotape made by one of the nurses of the hospital, the Mass Bay medical center survived the initial nuclear attack that devastated the Greater Boston area. According to the same holotape, the medical center was then commandeered by the military and continued to treat patients for some time. The situation quickly deteriorated and the medical staff could do nothing but try to make the patients comfortable. Sometime after the bombs dropped, a military Vertibird crashed into the roof of the hospital. Centuries later, the skeletons of US military soldiers and former patients remain scattered throughout the building, and the Gunners have now comandeered the center for themselves.
The layout for Mass Bay is mostly vertical, except for the first floor which is broken into two sections and the second floor which spans multiple hospital departments. The first four floors are in a different interior cell than the other floors, so if all enemies have been cleared, the Sole Survivor can freely move around without alerting enemies on the remaining floors.
The main entrance opens into a 2-story lobby. The Sole Survivor will be facing east upon entering. To the south is a police Protectron and the Expert terminal that controls it sits behind the nearby desk. East of the lobby are some broken elevators to the north and restrooms to the south. Further east is a kitchen and a fortified cafeteria with a cooking station and a Gunner who may be doing push-ups if one sneaks up on them. To the south of this area is another entrance into the medical center. Back to the lobby, to the north is a set of stairs leading to the second floor, but is blocked beyond that.
The other part of the first floor consists of the emergency room entrances and lobby. The main emergency room entrance is to the west, and another entrance can be found across the room to the east. To the south is another broken elevator that houses a turret. Near the elevator is a staircase leading to the second floor.
Starting from the main entrance staircase, to the south is an Assaultron and/or a leveled Gunner who patrols the area. From this main area, there are paths to the east, southeast, and south. Southward is the emergency side of the hospital, including the staircase down to the first floor to the west and exam rooms to the east. To the east is another small lobby and multiple exam rooms, one of which has a chemistry station. Further to the east is a medic Protectron controlled by a Novice terminal right next to it. There are two locked exam rooms - one is Expert locked and contains a gruesome scene, the other is Novice locked and has an Addictol.
Back to the main area, the eastern path closest to the staircase leads down a hallway that curves to the south. Around the corner lies another turret protecting yet another entrance into the medical center. This entrance is reached by taking the wooden stairs that circle the building on the outside.
Main area - the southeastern path leads into a room with two cells, one of which contains a dead Minuteman. Behind the nearby desk is a Novice terminal which can open the Novice locked safe just below. Continuing on leads one into a room where the third floor has collapsed, creating a path up. It also contains several curtained beds that contain various things like a chemistry station and ammo.
Going up the collapsed floor path leads to some rooms including two lab-type rooms and a small office. Beyond this is another reception area with two broken elevators and a skull in a carriage. The staircase that was blocked from the second floor is now clear and can be used to reach the fourth floor.
Yet another reception area. Here there are doors leading to a new area, Medical Center Station North, and a working elevator. There is a Slocum's Joe coffee shop at this juncture, spread across a seating area on the lower tier and cashier and counter on the second tier. The elevator leads to the floor above.
The elevator opens up to the seventh floor. The floor goes to the right of the elevator, or east, and opens up into a three-story atrium. There is a Gunner commander on the eighth floor directly east who will try to enter a suit of power armor just north of them if one is detected. There is also likely another Gunner on the ninth floor. Various collapsed floors create ramps leading to the next story in the building. Take seven to eight, then to nine.
A set of leveled[verification overdue] power armor will be present on this floor, and is the same one that the Gunner commander will try to enter should they make detect enemies arriving on the floor. There are two power armor stations found here.
At the top of the ramp coming from the 8th floor is a bed. To the west on this floor are some more cells. One contains a dead Brotherhood of Steel scribe. To the east is a room with a collapsed ceiling heading up or a hallway leading further back. If one heads back, one will find an MRI machine and some offices, one of which contains a Novice safe. Once done with the area, the player character may take the collapsed ceiling to the tenth floor.
On this floor, there is an elevator leading to the roof.
On the roof is a small living area with various junk items and drugs, and a U-turn from the elevator leads to a MILA drop point. There is also a window cleaning elevator that leads to the Ticker Tape Lounge. One can also see the vertibird that crashed into the building, which created a path to the other roof.
- Syringer - On a countertop in the northeast corner of the second floor.
- Vault-Tec lunchbox - On a couch next to a baby stroller, in the waiting area on the third floor.
- Power armor - On the eighth floor. The two Gunners nearby might try to enter it when alerted to the player character's presence.
- Bonnie's holotape - In the control room for the MRI scanner, in the northeast corner of the ninth floor.
- Weathervane: Tinker Tom asks the Sole Survivor to place atmospheric sensors on high vantage points to detect any anomalies in the air.
- The chest x-rays are all hung backward, with the heart on the left side. They are normally hung as if facing the patient, with the heart on the right. An x-ray can be taken from the front or back, with an "L" or "R" placed in the corner to show orientation. The artist seems to have hung this x-ray so the "L" reads forwards, rather than putting the "L" on the right.
- The power armor suit on the 8th floor will never improve past T-45f regardless of player character level. It may also spawn with its helmet on rare occasions, as well as with random paint jobs applied to some pieces.
- On the top-most floor, there is a window cleaning elevator that can allow access to the Ticker Tape Lounge. However, upon entering the Ticker Tape Lounge and returning, the elevator will have returned to the top with no way of calling it back down. Simply fast travel out of the location if the elevator "disappears."
The Mass Bay medical center appears only in Fallout 4.
Behind the scenes
Sometimes, when one enters the elevator to the roof and presses the elevator button, the elevator will close but then run forever, seemingly passing unlimited floors without end. [verified]
- This may be related to the positioning of the player character and their companion when starting the elevator. Having your companion get in first and move to the back of the elevator, and then issuing the stay command, will normally prevent the bug from occurring. The elevator should pass about four floors on a regular trip - if yours goes beyond 5 or 6, you've likely encountered the bug. Jumping around inside the elevator might cause it to become "unstuck."