160717-N-QO326-001 PACIFIC OCEAN (July 17, 2016) Chinese Navy guided-missile destroyer Xi’an (153) fires the main gun during a gun exercise at Rim of the Pacific 2016. Twenty-six nations, more than 40 ships and submarines, more than 200 aircraft and 25,000 personnel are participating in RIMPAC from June 30th to August 4th, around the Hawaiian Islands and Southern California. As the largest international maritime exercise in the world, RIMPAC provides a unique training opportunity that helps participants foster and sustain the cooperative relationships that are critical to ensuring the safety of sea lanes and security on the world's oceans. RIMPAC 2016 is the 25th exercise in the series that began in 1971. (Chinese navy photo by ZhuLiang Wenxuan)