Outside the building is a pre-War plaque and a Freedom Trail marker. The location is the second stop on the Freedom Trail, with the code "4:L." A Novice-locked safe is in the small ruined eastern wing.
Inside, the entrance area is a destroyed facility full of mirelurks and mirelurk hatchlings, along with dead raiders. The only available route is up a ramp formed by the collapsed ceiling to the east, which leads through a series of derelict rooms on the second floor, one of which has a terminal previously used by the Treasurer and a cooking station. A pair of short stairways to the south descend to a room with two lion statues. Proceeding west then south through more rubble-filled rooms leads to a collapsed ceiling ramp heading back up to the second floor. The path east once again returns to the first floor down a ramp, with the building's central large atrium to the west.
In the middle of the atrium is a hole leading down into the partially flooded basement area. By falling through the hole, one will enter a large chamber with a pair of closed security doors to the south and a hallway to the west. The hallway leads to a large storage room full of shelving and radioactive barrels, followed by a room with broken pipes, and finally a room with a terminal and a generator. One can open the security doors across the large chamber to the south via the terminal. Returning to the central chamber will result in a mirelurk queen emerging from the pool of water.
Through the southern doors is a room full of radiation followed by a hallway. To the west is a room with a bottlecap mine and a terminal previously used by a maintenance technician, while to the east is a room with three frag mines and an Expert-locked safe. A unique mirelurk encounter triggers in the hallway, with the mirelurk tunneling up through the floorboards until finally emerging at the western end of the corridor. Past the room with the frag mines and safe is a trapped corridor and a ramp leading up into the raider base. The base spans the first, second, and third floors, with a weapons workbench on the second floor, and an armor workbench, two bottlecap mines, and the raider leader on the third floor.
On the third floor, through the Master-locked door is a room containing one or more raiders, as well as a sniper rifle and some ammo. The hole in the wall leads to a wooden walkway above the atrium. Across the walkway to the north and through a series of rooms is a final room with the raider leader, another raider, a turret, an attack dog, and a steamer trunk. To the west is an elevator that heads back down to the second floor in the entrance area.
The building also features a hidden room with a skeleton surrounded by three teddy bears and a dose of Psycho. To access the room, one must have a jet pack. The room is to the east, through a hole in the ceiling above the ramp on the second floor descending to the first floor and the atrium. Approaching the skeleton will trigger a chilling piano note.
- State House note - On the second floor, on a dead scavenger in the room with the cooking station.
- Overdue book - On the first floor, leaning against the side of a desk with the lieutenant governor's terminal in a room with a partially collapsed ceiling and a mattress northwest of the room with the two lion statues.
- Mirelurk eggs - In the basement, in the room with broken pipes.
- Fusion core - In the basement, inside the generator in the room with the terminal that opens the security doors.
- Raider atrium key - On the third floor, in a metal box in the enclosed area behind the turret to the southeast. Opens the Master-locked barricade door to the north.
- Vault-Tec lunchbox - On the third floor, on a wooden crate east of the table with three chairs and several loose caps in the room before the raider leader.
- Raider power armor - On the third floor, on the raider leader in the final room before the elevator.
- Mini nuke - On the third floor, on a bookshelf in the final room before the elevator.
- Road to Freedom: The Sole Survivor has heard of a group that aims to take on the Institute and only has the clue, "Follow the Freedom Trail." To find the Railroad, they have to start at Boston Common.
Without a jet pack, once the player character jumps down the large hole in the atrium to the flooded chamber, they will be forced to advance through the mirelurk-infested basement and upward through the subsequent raider base in order to be able to exit the building.
The Massachusetts State House appears only in Fallout 4.
- Fallout 4 Vault Dweller's Survival Guide p. 471: "MASSACHUSETTS STATE HOUSE"
"The “new” state house was completed in 1798 to house the government of Massachusetts State. The land selected was originally John Hancock's cow pastures. The first dome was constructed of wooden shingles and covered in copper smelted by Paul Revere. The state government used this building continuously until the formation of the Thirteen Commonwealths in 1969. This is part of the Freedom Trail. The number “4” is daubed on the circular ground plaque pointing at the letter “L.” Outside, one corner of the structure has collapsed, allowing lock-fiddlers the chance to open a wall safe (Novice)."