Hillside Assault A Marine guides ammunition as U.S. and Spanish Marines conduct a vertical assault during Spanish Amphibious Exercise in Sierra del Retin, Spain, March 14, 2017. The U.S. Marines are assigned to 3rd Battalion, 6th Marine Regiment, 24th Marine Expeditionary Unit, which is supporting maritime security operations and theater security cooperation efforts in the U.S. 6th Fleet area of operations. The exercise aims to enhance interoperability and sustain tactical skill sets. Marine Corps photo by Lance Cpl. Autmn Bobby SHARE: Download: Full Size (1.85 MB) Credit: Lance Cpl. Autmn Bobby VIRIN: 170314-M-EU132-157C.JPG Photo Gallery