The Castle

The Castle is the former headquarters of the Minutemen in Boston in 2287. It is a possible settlement, and can be reclaimed during the Taking Independence quest. It is built into Fort Independence and is located to the east of the Gwinnett restaurant and brewery.

Background
Before the War, it was known as Fort Independence. The Minutemen repurposed it as their headquarters in The Commonwealth until a colony of mirelurks forced them out in 2240 and took it as their nest. Preston Garvey asks the Sole Survivor to reclaim the Castle for a new generation of Minutemen.

Once the main stronghold of the Minutemen, The Castle is a potential settlement for the player, but it is teeming with mirelurks and houses a mirelurk queen. These enemies must be defeated before the player can begin to build and attract settlers.

Layout
Fort Independence is a star fort, consisting of five triangular bastions connected by walls. The walls are hollow and contain most of the fort's infrastructure, with only the workshop and the Radio Freedom transmitter out in the courtyard and two ruined gun positions on the walltop. The northwest and southwest walls have been all but demolished, and a sizable hole punched in the south wall as well, cutting off the west bastion--which contains the Castle armory--from access excepting through the Castle tunnels. The north bastion contains the Castle kitchen; the east, the General's quarters and access to the Castle Tunnels; the southeast, the barracks. The southwest bastion is completely inaccessible.

The Castle is initially occupied by a large group of mirelurks, and piles of mud studded with mirelurk egg clutches can be found all over the courtyard and all interior areas save the armory. Once the quest Taking Independence is completed, these will be cleared away and the fort made available for settlement.

Inside the fort is a Missile launcher and flamer, as well as a small amount of ammunition for each. Once settled, it comes with five free beds, a medic stand, chemistry workbench, starter lighting and electrical cable system, and an industrial water purifier good for 40 units of water should the player reintroduce power into the system.

Inside the Armory is a cache of heavy weapons, a weapon and armor workbench, and three free laser turrets that can be stored or redeployed elsewhere using the workshop menu. Also present are the schematics for building the special artillery units. However, access to the Armory is impossible until the quest Old Guns is completed.

Access to the Castle settlement is done from the south via the main gate, and enemies will attack from this direction; behind the gate is a small and highly defensible room, which combined with the Castle's high and easily repaired walls makes it one of the safest settlements in the Commonwealth.

Notable loot

 * Guns and Bullets issue #10 (+5% ballistic weapon critical damage) - On the radio operator’s desk, in the middle of the Castle grounds, outside. Confirmed during Old Guns mission. Confirmed during Taking Independence mission.
 * Fat Man - In the armory accessible during/after Old Guns.
 * Various laser musket upgrades in the armory.
 * Minutemen general's uniform - In the Castle tunnels during the quest Old Guns.
 * Minutemen general's hat - In the Castle tunnels during the quest Old Guns.
 * Fusion core - In the charging slot of a generator, in the Castle tunnels during Old Guns quest.
 * A flamer along with a large amount of fuel can be found scattered throughout the Castle.
 * Preston or any of the Minutemen may take the flamer when fighting against the mirelurks.
 * Missile launcher, along with some missiles scattered throughout the Castle.
 * Nuka grenade - on top of one of the shelves
 * Bottle message #2 - Located near the south-southeastern star point by the water's edge. The submerged boat and the lootable steamer trunk for the objective is located just northwest of Spectacle Island.

Appearances
The Castle only appears in Fallout 4.

Behind the scenes
Toward the end of The Castle tunnels, near General McGann's body, is a crate of Amontillado wine. Opposite the wine is a skeleton seemingly entombed in a wall. This is a reference to Edgar Allen Poe's story The Cask of Amontillado. While he was serving at Fort Independence, Poe noticed a gravestone in the fort's cemetery dedicated to Lt. Robert Massie, who died on Christmas Day in 1817. The other soldiers told Poe that Massie had been killed in a duel with another officer, Lt. Gustavus Drane. Drane had never been popular with the enlisted men at the fort, and what little popularity he had vanished after he killed Massie. One night when he was drunk the soldiers lured him into the basement of the fort and walled him up alive. The duel really did happen, but Drane was court-martialed, acquitted, and died in 1846. Years later, Poe used this incident as inspiration for "The Cask of Amontillado." The label of the Amontillado Bottle reads "Montressor, Amontillado, Bottled by: P. Edgar" again a direct reference to the work of Poe.

Bugs

 * The Minuteman in charge of broadcasting Radio Freedom may complain that the transmitter is not being powered despite having power, usually after starting the Old Guns quest. This is accordingly due to the Minuteman becoming hostile to Sarge in the Castle tunnels and so should be able to be prevented by eliminating Sarge before Old Guns. Otherwise, this prevents use of Radio Freedom.
 * When building generators to power the beacon, the beacon will show the power requirement not being met regardless of how much power is being supplied to it and as a result, will not activate. This can usually be fixed by removing each generator, storing them, and replacing them.
 * Assigning guards to guard towers can be problematic, since they seem to follow a totally random patrol route to nonexistent guard towers that seem to already be in place when you take The Castle.