Located at the heart of Utah, Salt Lake City was heavily bombarded in the Great War. Over the span of just seven minutes, thirteen nuclear weapons hit the city, turning it into a sea of fire and destruction. When the fires finally died down, the city was left a smoldering ruin. It was a landscape of craters and scorched earth, punctuated by warped steel skeletons of highrises and mounds of bricks where buildings would normally stand.
↑The Courier: "Why can't you get to Salt Lake City?" Jed Masterson: "Without New Canaan's mission in Zion, the only ways to Salt Lake City are down the old I-80 or up through Ogden. The highway's too risky - NCR's rangers are so busy here in the Mojave they don't have the manpower to keep the raiders off. Ogden's just too far - we'd lose more in travel expenses than we'd ever earn." (Jed Masterson's dialogue)
↑Fallout Bible 0, Answer me these questions three: Known species that can reproduce after being mutated with the FEV include most species of rats, the mantises (who are known to have bred so fast they cover the Salt Lake City area like blankets), the radscorpions, and the deathclaws. This is only a partial list.