Crucible Carry Marine Corps recruits participate in a Crucible event at Marine Corps Recruit Depot, Parris Island, S.C., Jan. 10, 2020. The Crucible is a 54-hour field training exercise that presents continuous physical and mental challenges. SHARE: Download: Full Size (2.55 MB) Tags: Marine Corps Credit: Marine Corps Lance Cpl. Christopher McMurry VIRIN: 200110-M-BK403-1141A.JPG Photo Gallery