U.S. Marines with 1st Battalion, 25th Marine Regiment, 4th Marine Division, hike to Range 220 during Integrated Training Exercise 5-19 at Marine Corps Air Ground Combat Center Twentynine Palms, Calif., July 30, 2019. ITX 5-19 is an essential component of the Marine Forces Reserve training and readiness cycle. It serves as the principle exercise for assessing a unit’s capabilities. (U.S. Marine Corps photo by Lance Cpl. Jose Gonzalez)