Most survival plans involve going somewhere else. "The mountains" or "the country" are popular. This is probably because the people most worried about SHTF are in urban areas that are not self-supporting.
Unfortunately, almost everyone seems to plan to go to the same places.
Historically, the prime living areas have been near water. Even a small lake can provide food and fresh water. Rivers do that, and offer easy travel as well. Seaside areas with ample fresh water nearby aren't as common as you'd think, and the best areas already have cities squatting on them, but any place you can safely land a boat at can be a source of food.