Diamond City

Diamond City, commonly referred to as the "Great Green Jewel," is a large fortified settlement in the Commonwealth. The settlement was built within Fenway Park, a pre-War baseball stadium. Its distinctive green color visible on the tall, reinforced walls, earning the nickname of the "Green Monster."

Background
With the years of pre-War baseball at Fenway Park long past, Diamond City was founded in its stead during the 2130s. The settlement established itself as a safe haven for settlers of the Commonwealth, thanks to what its residents affectionately referred to as "the Wall." Later decades saw Diamond City grow into the Commonwealth's largest and most prosperous community. It developed a degree of social stratification as wealthier residents came to occupy properties in the settlement's exclusive upper stands. These overlooked the lower field where those with less means took up residence.

Post-War events
The stadium and those who live within have experienced several significant events after the war. In 2180, the Commonwealth Minutemen defended the city from an attacking horde of super mutants, causing the militia's rise to prominence. The Broken Mask incident occurred in 2229, when a visitor named Mr. Carter opened fire at a centrally located Diamond City bar, killing several citizens. Security personnel killed Mr. Carter, and upon inspecting his remains, discovered he was a synth.

This caused the beginning of wide spread fear and paranoia surrounding the Institute. Since the event, the fear has only escalated due to subsequent unexplained disappearances of citizens such as Becky Fallon's husband Charlie.

In 2272, a new restaurant named Power Noodles was established, with a Protectron known as Takahashi at the helm. In the following years, the restaurant became a staple of Diamond City culture. The end of the decade was marked by the controversial election campaign of McDonough, centering on the expulsion of all ghouls from the city. Upon his election to office in 2282, he declared the enforcement of the new anti-ghoul decree, subsequently seeing to the eviction of all ghouls from the city.

By 2287, some residents came to believe McDonough had been replaced by a synth, a suspicion exacerbated by Piper, her sister Nat and their newspaper Publick Occurrences.

When Piper reaches idolized status with the Sole Survivor, she explains that when she first moved to Diamond City with Nat, the Great Green Wall was broken and patched with a solitary bookcase. This drove her to create Publick Occurrences to address the issues of Diamond City.

Layout
The city is split into social classes where the rich and powerful reside in the upper stands, whilst the common people, both housed and unhoused, live in the field below. The center of the city is the marketplace, which is approached by the main entrance stairs from the south. Surrounding the marketplace are four main streets laid out along the old baselines: First Street on the south side, Second Street on the east side, Third Street on the north side, and Home Street on the west side. The least wealthy residents sleep under shelters in the area north of Third Street, where they tend a small number of crops. At the north side of the city there is an auditorium area, a larger crop field, and brahmin pen. There is also a small irradiated lake to the east of Second Street, where the city's water is purified and sold.

Food can be harvested from the small and large crop field, or from the greenhouse building, or bought from vendors. Purified water can only be obtained from vendors. All types of standard crafting station are available for use in the marketplace. A bed may be rented at the Dugout Inn, or by obtaining access to either Home Plate or Kellogg's house.

Notable loot

 * RobCo Fun - Zeta Invaders - In Nick Valentine's Detective Agency on the furthest back desk.
 * Live & Love - I Married A Robot magazine - In the schoolhouse, downstairs by the beds.
 * Big Boy - This unique Fat Man that fires an extra projectile can be purchased from Arturo Rodriguez at the weaponry stand in Diamond City market.
 * Old Faithful - A unique laser pistol that can be purchased from Arturo Rodriguez at the weaponry stand in Diamond City market.
 * Protector's armor - Sold by Arturo Rodriguez.
 * Rockville Slugger - Sold by Moe Cronin.
 * Wastelander's chest piece - Sold by Myrna or Percy.
 * Champion's chest piece and right arm - Sold by Becky Fallon.
 * A Hazmat suit is frequently sold by Becky Fallon.
 * Red leather trench coat and Press cap - Both worn by Piper Wright.
 * Geneva's ensemble - Worn by Geneva.
 * Mini nuke - Inside Arturo's house, turn left and it's sitting on a table across from the bed.
 * The holotape Gwinnett ale brewing subroutines can be found in the Colonial Taphouse, on a shelf behind the bar.
 * A copy of the Join the Railroad holotape may be found in a bedroom near the kitchen of the Dugout Inn. It will be on a nightstand next to an alarm clock.
 * Another copy of the same tape can be found in Abbot's house on a shelf when entering the house.
 * Yet another copy can be found on the top floor of Fallon's Basement.
 * Several Nuka-Cola Quantums scattered throughout the city:
 * Two are located around Power Noodles.
 * One is found in Polly's house, sitting on an end table.
 * One is next to where Sheng Kawolski stands while selling water, on the metal shelves to the right.
 * Two are in the hidden room in Kellogg's house on a shelf.

Companion comments

 * When at this location companions make comments.

Appearances
Diamond City appears only in Fallout 4, and is mentioned in Zoe's diary in the Automatron add-on and by Lizzie Wyath in the Nuka-World add-on. It is also mentioned in a question in the Fallout Shelter weekly quest Game Show Gauntlet.

Behind the scenes

 * Nathan Purkeypile designed much of Diamond City's layout, lighting, and cluttering. It was the first location that he worked on for the game, as the developers knew from the beginning that they wanted iconic stadium lights and that the main quest would point towards it as a "beacon" or landmark that could help the player navigate the city.
 * Atop the press box, there are five red flags reading "World Series Champions" with the years 1903, 1912, 1915, 1916, and 1918. This implies that following the Divergence, the Red Sox never won the World Series again and the Curse of the Bambino was never broken. In the real world, the Red Sox finally won the World Series after an 86-year drought in 2004.
 * According to the left-field bleachers, the team's retired numbers in the Fallout universe were 1, 4, 6, 11, 13, 21, and 33. Of these, 1, 4, and 6 are actual retired numbers.
 * Diamond City resident Moe Cronin bears a name near identical to former Red Sox player Joe Cronin, owner of one of the aforementioned retired numbers. Ironically, Moe's idea of what the sport of baseball is and how it's played is comically skewed.
 * The Wall is based on the real world location of "the Wall" or "Green Monster," popular nicknames for the 37 foot (11.33 m) left field wall at Fenway Park.
 * In the real life Fenway Park, there is a large Coca-Cola sign approximately in the same location and style as the Nuka-Cola sign in game.
 * Likewise, the Mass Fusion billboard mounted on a building behind the Wall mirrors the placement of a large advertisement for the Citgo gasoline company made of neon lights. The real sign was rigged so that it could light up the letters C, IT and GO in sequence ("See it go") when a home run was hit.
 * There is a single red seat in the bleachers, representing where Ted Williams hit the furthest ball in Fenway Park history, 502 feet from home plate.

Bugs

 * When using the elevator to the mayor's office with a companion the companion can end up at the first green trash can when you enter Diamond City, behind the street light in front of the elevator and be stuck there. Walking outside of Diamond City to the Fens (manually without fast-travel) will sometimes work to free a companion in this frustrating situation.
 * For PC players, utilizing after selecting the companions ID can rectify this issue.
 * Occasionally, if the player activates the elevator on the way down from the mayor's office, and before the elevator reaches the bottom floor, activates the second button, the guard rail will extend, as if the player were to disembark and retract upon arrival as if the player is riding the elevator.
 * Activating the elevator and leaving Diamond City or entering a building before the elevator stops moving and reload the game may fix this. On PC Using to noclip through the exit will make this easier.
 * Putting any items in mailboxes, even the one in front of the Sole Survivor's Home Plate residence, will show as owned upon closing the dialogue box. Stealing is the only way to access said items.
 * After completing the quest Unlikely Valentine, two triggermen may spawn in Diamond City each time you travel to the city. Most of the civilians in Diamond City will engage. As of now, there is no fix.