As its name suggests, Radiation Valley is a lowland between two hills, containing dangerously high levels of gas radiation. Players entering the affected area without adequate protective gear are exposed to high levels of radiation. A fully unprotected player without any radiation resistance bonuses will receive a 1% increase to their Radiation Status bars per second.
Radiation Valley is characterised by the presence of dead trees and grass, which also form a visual representation of the boundaries of the high radiation area. Ionizing radiation hazard signs are placed along road that leads through Radiation Valley.