For the setting of the third annual L.A. 13.1 Marathon, the race organizers have chosen the city's famed Venice Beach Boardwalk, where the race will start and take runners and walkers on an L-shaped course that follows its first mile along the boardwalk and then turns onto Venice Boulevard. The course then follows a long straightaway run for the next five and a half miles or so up along Venice Boulevard, to the turnaround point in Culver City. <p> After making the turn, runners then head back along the route they've just run, back toward the Pacific Ocean and through neighborhoods including Mar Vista and Palms, turning just before they make it back to the boardwalk area onto Main Street for the finish, just blocks away from Santa Monica Beach. <p> The race will be run on paved streets throughout, and runners and walkers (who will start after the runners and are asked to be able to complete the race within three and a half hours) will find the course follows a long, gradual uphill for the first half of the race along Venice Boulevard, followed by an equally gradual downhill through the second half of the race back toward the finish line.