>>715455881
im playing fallout 3 again right now
megaton's crater was caused by a bomber plane crashing (not the atom bomb in the center of the city)
before the city was built it's claimed that the crater was a desirable spot for wasteland traders to hide from dust storms
the city & its walls were built out of the remains of the plane + some other debris from other planes from an airstrip north of megaton
the walls in particular were necessary to keep raiders out

there are perfectly serviceable homes up in the town of Minefield that just need some corpse removal, however, the reason those homes aren't inhabited is because there's no real protection from raiders, and there's a crazy guy with a sniper rifle throwing frag mines all over it.