Recently, I read a potboiler on the End of the World. I was intrigued to find, however, that it was the second novel that I had read in the space of a year to mention Mount Weather as part of the plot.
Mount Weather, as the link about will tell you, is a small bomb shelter facility near Washington D.C. deigned to help U.S. government officials survive a nuclear attack. Its status as secret notwithstanding, we do know that Mount Weather is relatively small and spartan. However, according to the novels that I read, Mount Weather is the space of a small city with its own subway and even a manmade lake.
Let's hope that Mount Weather becomes obsolete, shall we?