Children wait for the start of the Marine Corps Marathon Kid’s Run Oct. 24, 2015, at the Pentagon in Arlington, Virginia. More than 3,500 Children participated in the one-mile event. The run is organized to promote physical fitness and morale for the children and the community. - Children wait for the start of the Marine Corps Marathon Kid’s Run Oct. 24, 2015, at the Pentagon in Arlington, Virginia. More than 3,500 Children participated in the one-mile event. The run is organized to promote physical fitness and morale for the children and the community.