Join fellow runners for this fast and flat 13.1-mile out-and-back course taking place on Labor Day Monday, September 7, 2026, starting from Marymoor Park in Redmond, WA. The route heads west from the park and north along the Sammamish River Trail before looping back to the finish, making it an ideal opportunity whether you're tackling your first half-marathon or you're a seasoned runner looking to hit your goals. Organized by Lake Sammamish Run Club and Seattle United Runners, this local event is the perfect way to cap off your summer of training.