Anyone with two brain cells to rub together can pull out a map and find Yosemite, say, or the River of No Return Wilderness. It takes an open, inquisitive mind to find a pocket of wilderness that isn't officially designated, particuarly in the city. Here are three hints.Redefine 'wilderness' and the time you spend there. Instead of reserving hiking for the times you manage to travel to a quarter-million contiguous acres of pristine Alaskan forest,...