Marines with 4th Assault Amphibian battalion drive an amphibious assault vehicle during a simulated amphibious assault at Peninsula Express 15-8 on Dogu Beach, July 3, 2015. Peninsula Express is the eighth iteration this year of the Korean-Marine Exchange Program, and the first time Marine Forces Reserve has participated in the series of exercises between the U.S. and Republic of Korea Marine Corps designed to build interoperability and tactical familiarity between partner nations. - Marines with 4th Assault Amphibian battalion drive an amphibious assault vehicle during a simulated amphibious assault at Peninsula Express 15-8 on Dogu Beach, July 3, 2015. Peninsula Express is the eighth iteration this year of the Korean-Marine Exchange Program, and the first time Marine Forces Reserve has participated in the series of exercises between the U.S. and Republic of Korea Marine Corps designed to build interoperability and tactical familiarity between partner nations.