Mount Weather.
en.wikipedia.org
Seriously, a functioning democracy (not convinced the US is one anymore but lets go with it) needs to transition its representative power in public, or at least visible to it via video. If it is done in secret, those that chose to disrupt democracy win a victory. Ya gotta know the joint security task force is working late nights, going through lots of coffee and will have some seriously disrupted sleep until Wednesday. The site will make the G20 security look like summer camp.