Coastal artillery is the branch of the armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications.
From the Middle Ages until World War II, coastal artillery and naval artillery in the form of cannons were highly important to military affairs and generally represented the areas of highest technology and capital cost among materiel. The advent of 20th-century technologies, especially military aviation, naval aviation, jet aircraft, and guided missiles, reduced the primacy of cannons, battleships, and coastal artillery. In countries where coastal artillery has not been disbanded, these forces have acquired amphibious capabilities. In littoral warfare, mobile coastal artillery armed with surface-to-surface missiles can still be used to deny the use of sea lanes.
