Megaton

 is a sprawling settlement south of Springvale and west of Grayditch, set in a crater and surrounded by impenetrable walls. It is one of the two largest civilian settlements in the Capital Wasteland, with 28 named inhabitants, and several Megaton Settlers.

Megaton should be the first populated town the player encounters after leaving Vault 101. Its proximity to Vault 101, its distinctive silhouette, and the relatively straight route make it extremely difficult to miss, and it will very likely be the first trace of civilization the Lone Wanderer encounters.

Background
Megaton was built by a large group of people who originally planned to seek shelter in Vault 101 but were denied access. Without shelter, they sought refuge in a large crater made by a large aircraft crashing into the ground. It is possible that a military cargo aircraft overladen with the bomb and other payload created the crater. The settlers constructed a place to call home out of pieces of metal/aircraft found nearby at a decimated airport. (presumably either one that no longer exists as implies, or potentially fort adams air base, which would have seemed to have vanished after the enclave locked down the area, most likely over time. They were aided by the Children of Atom, who worshiped the undetonated bomb in the crater they were building around.

The plane
The large plane still can be seen in pieces throughout the town. The cockpit and nose cone are built into Craterside Supply apparently housing inaccessible living space to Moira. The main section of the fuselage is used as the armory, and the rear end of the plane is on the roof of Lucas Simms' house providing an extra sniper nest and speculated residence to Stockholm. You can get there via a trap-door in the ceiling of the Sheriff's house. The wings make up the two large "fins" that are symmetrically aligned next to Megaton's main gate, and the two engines are separated. One is used to work the pulley mechanism for the main gates, and the other one is above the path to the common house providing breeze. Also smaller ramps can be seen at the left side of the crater going to Lucy West's house, and above the clinic heading to Craterside Supply, probably 2 side wings. If you ask Manya about it, she will respond that the Plane made the huge crater. And that some of the people there went to an old airport to get more materials. Finding the airport is impossible, Manya mentions that "The wasteland took it back".

First contact with Vault 101
In February 2241, an expedition party sent by the Overseer of Vault 101 contacted the residents of Megaton. Initially, the residents were cautious with these strangers before they eventually accepted and welcomed them into the settlement. Two Vault residents, Agnes and Lewis, were appointed as Vault ambassadors to Megaton by the expedition leader Anne Palmer. A record of this expedition was archived in the Overseer's terminal.

Boppo's raid
In 2277, a gang of Raiders established a base camp at Springvale Elementary School, with the purpose of mining their way into Vault 101. Some of these gang members, led by Boppo attempted a raid into Megaton. The attack ran afoul of Megaton's defenses and her determined defenders. The town's sheriff, Lucas Simms, killed the leader of the raiding party.

Layout
Megaton is roughly circular, with a central plaza around an atomic bomb resting in a puddle of radioactive water. Starting in the north and proceeding clockwise, the plaza is ringed by The Brass Lantern, Mister Burke's House, Children of Atom, and Megaton Clinic. Pathways lead from the plaza to the gate of Megaton, Craterside Supply and the Common House. A major attraction of the plaza are the sermons of Confessor Cromwell.

Around the central buildings, a ring of buildings is built higher up in the crater. The Water Processing Plant and Moriarty's Saloon can be found here along with most of the inhabitants' private houses.

It seems the left side is where the town people live, and the right side with factorys and shops.

Notable loot

 * Bobblehead - Strength - inside Lucas Simms' House, on a desk in a bedroom on the second floor. To avoid bad karma; wait until Lucas is in his home, so you don't have to pick the lock of the front door.
 * Grognak the Barbarian - in Jericho's House, on the floor, between a teddy bear and a red pylon. You have to steal this item.
 * Nikola Tesla and You - in your Megaton home after buying the Science Theme from Moira Brown.
 * Lying, Congressional Style - in your Megaton home when you buy the Love Machine Theme from Moira Brown

Related quests

 * Following in His Footsteps
 * The Power of the Atom
 * The Wasteland Survival Guide
 * Treatment
 * Walter's Scrap Metal
 * Church Donations
 * Leo's Drug Habit
 * Blood Ties
 * The Replicated Man
 * Holy Water (Broken Steel)

Appearances
Megaton only appears in Fallout 3.

Behind the scenes

 * The bomb in the center of the town and the people worshiping it are likely a reference to Beneath The Planet of the Apes, which features a cult worshiping an unexploded nuclear weapon.

Japanese version
In the Japanese version of Fallout 3, the quest to blow up Megaton has been completely removed due to its "parallels to real historic events" quotes Official Xbox Magazine. They are referring to the atomic bombs that were dropped on Hiroshima and Nagasaki in 1945.

Gallery
Мегатонна Megaton Megaton