Cabins in tbe Catskills, apparently. This post on Time Magzine's Battleland Blog (a really good source of interesting and informative reports on the US military) highlights an effort to sell folks in NYC on bugging out to the Catskills during a crisis.

I'm making no judgements about the marketing plan but I think we'd all be better off in spending time and energy in fixing the root causes of our problmes than looking for root cellars.