Nearly 430 troops from the Army Capital Corps and the 2nd Marine Division attended the drill held at a shooting range in Cheorwon, 85 km northeast of Seoul.
The artillery exercise mobilised 30 units of K9 and K55A1 self-propelled howitzers, as well as counter-battery radars and surveillance drones, Yonhap news agency reported.
It was aimed at bolstering the combined operability of the Army and Marines to better deter threats posed by North Korea, the armed service said.
North Korea, which has one of the world's largest artillery forces, has many long-range artillery pieces stationed within striking distance of the wider capital area -- home to nearly half of South Korea's 50 million people.
