A settlement established by the raiders, Crater was built in the ruins of the Valiant-1 space station, which lost optimal orbit as time passed after the Great War and crashed into the Toxic Valley. Although the raiders had been in Appalachia previously as five different factions: the Cutthroats, Gourmands, Blackwater Bandits, Diehards, and Trappers, all of their previous camps and hideouts had been abandoned when they were forced to flee or were killed by the Scorched. Word of the region being recolonized by the Vault 76Vault Dwellers convinced the raiders, now led by Meg, to return and set up their new home base at the crashed space station in the Toxic Valley.
The Crater is located in a large, shallow crater near the northeastern edge of the Toxic Valley. The space station appears to have fallen from orbit at a high velocity, devastating the surrounding area. The bulk of the station remains embedded upright in the center of the crater, with fragments scattered around it.
By 2103, the location has been turned into a raider settlement, adding scaffolding, amenities, and other decorations typical of raider architecture. The Crater Core is located in the center of the spaceship and has been turned into the raiders' headquarters.
The real-world counterpart never got off the design and model stages created by Werhner von Braun in 1950. It used the theory proposed by Konstantin Tsiolkovsky that a spinning ring could be used in a weightless environment to create artificial gravity that would be controlled not only by the size of the ring, but by how fast it would spin. NASA has toyed with the concept since 1975, but to date no one has constructed one, unless the Space Station X-1 attraction built by von Braun and Walt Disney in 1955 is counted.
In the real world, a space station reentering earth's atmosphere would be torn apart by friction and deceleration. Sixty to ninety percent of its mass would burn away, and whatever remained would rain down over an area of several hundred miles.
The following is based on unverified behind the scenes information and is speculative and may not be accurate.
↑Nate Purkeypile on Twitter: "Various settlements I have made on the Fallout series over time. / Also, to clarify, I did the layout, lighting and cluttering. So not just the world art side of things. I enjoy thinking about how a city is laid out and functions. Designers handled the actual NPCs, quests and dialogue."