Imperial beach is just off the 5. A little below "Chula Juana". Close to the border, where you get to watch illegals walk out of (or float by) the ocean from time to time. More of a beach/surfer crowd if you know what I mean, really hanging loose. Probably best to know your way around a little before getting into hanging around there. Lot of 2-3 day party's start from there and wind up in private homes in La Jolla, La Costa and other rich peoples places.