The recruits of Company E, 2nd Recruit Training Battalion, complete a six-mile sustainment hike around base May 12 aboard Marine Corps Recruit Depot San Diego. The sustainment hike helps prepare the recruits for the amount of hiking they'll complete on the Crucible, a 54-hour field-training exercise. More than 50 miles are hiked between obstacles during the culminating event. - The recruits of Company E, 2nd Recruit Training Battalion, complete a six-mile sustainment hike around base May 12 aboard Marine Corps Recruit Depot San Diego. The sustainment hike helps prepare the recruits for the amount of hiking they'll complete on the Crucible, a 54-hour field-training exercise. More than 50 miles are hiked between obstacles during the culminating event.