The Massachusetts State House is a location in the Commonwealth in 2287. The first part contains mostly miscellaneous loot and a couple of dead raiders, further down there is a mirelurk den in which a mirelurk queen can be found, and beyond that a raider base is situated.
The entrance area is a destroyed building full of mirelurks and mirelurk hatchlings. In the center of the building is a large atrium with a hole in the middle that leads down into the sewers. Drop down into the hole and you will see a pair of locked doors as well as a hallway off to the side. The hallway leads into a few rooms full of shelving and radioactive barrels, then eventually to a room with a fusion generator and a terminal. Activate the door locks via the terminal and the locked doors across the cavern will open. When you drop back down to the central area with the pool of water (or throw a grenade into the pool), a mirelurk queen will emerge. Before dropping down, grab the fusion core out of the generator.
Through the doors is a room full of radiation and then a hallway. The right hall leads to a room with another terminal, while the left leads to a room with mines and a safe, then a raider base. Note that the left hall also spawns a unique mirelurk encounter, with the mirelurk busting up the floor until finally emerging at the end of the hall. Continuing past the room with the mines and safe, there is a ramp leading up into the raider base. The base consists of several floors with a raider in power armor in a room near the top. The key to the locked Master door can be found in a metal box in the enclosed area behind the turret (around the corner from where the door is located).
Through the locked door is a room containing one or more raiders, as well as a sniper rifle and ammo. The hole in the wall leads to a walkway above the statehouse atrium with the hole down into the sewers. Across the walkway is a room with one or two raiders, a turret, a steamer chest, and an attack dog. One of the raiders is likely wearing power armor. In the room with the turret, there is a bookshelf with a mini nuke on it. In the corner is an elevator that will take you back down into the entrance area.
In the building there is also a hidden room with a skeleton surrounded by three teddy bears. To get to the hidden room you must have a jetpack (or use the tcl command in console (pc) - walking on walls glitch will not work here). The hidden room is situated to the east, through a hole in the ceiling in the room leading onto the main area where the mirelurk queen spawns (on the middle floor). The hole you must enter is above the sloped floor where the ceiling has fallen in. Approaching the skeleton will trigger a chilling piano note.
The “new” state house was completed in 1798 to house the government of the state of Massachusetts. 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.”
- Overdue book - Leaning against the side of a desk with a terminal on it, in a room with a partially collapsed ceiling and a mattress, west of the hall with 2 lion statues.
- Raider atrium key - At the raider base, in a metal box in the enclosed area behind a turret. Opens shack type door.
- Fusion core - On the bottom level, in the room with a terminal that opens a security door visible through a hole in the wall.
- Bottlecap mine - at the center of a room to the right after passing the security door and a room with irradiated barrels; another 2 not far from a container with Raider atrium key.
- Mini nuke - On a bookshelf in the room right next to the elevator.
- Raider power armor - On a raider commander, in the final room before taking an elevator back to the surface.
- Vault-Tec lunchbox - In the room just before the raider commander and turret due east of the table with three chairs and a bunch of loose caps on top.
- Day Tripper - In the northwest corner of the room that the elevator lowers you to - tucked behind the bookshelf.
- State House note - On a dead scavenger in a room with a terminal on the second floor.
The Massachusetts State House appears only in Fallout 4.