If you're opening to travel, I would suggest making a list of what you (and your son) are looking for in a camp. Is there a particular activity he likes or would like to try? Is a religious based program important, if so, how important? Do you want it to be an all boys camp or would you prefer a coed experience? I suggest looking at American Camp Association Accredited camps. Also program length is important. If your son is independent and does well away from home you could consider a two-week program. If he does not do well away from home then maybe try a day camp or a short one-week program closer to home. Take the list you compiled, search the web, call the camp offices and talk to the directors - these are things that will help you find a long-term camp home for your son.
I work for a camp in Minnesota (I may be biased), and I know there are a number of great summer camps in Minnesota with rich histories and ACA accredited. Minnesota's lakes and forests are the perfect setting for the camps as well.