weapons for discharging missiles, placed along the shore for defense against naval attack.

In the 15th century the Turks used coastal artillery when they positioned guns to defend the Dardanelles. By the 19th century all leading military powers had defensive artillery emplacements to protect their coastal cities, harbours, and strategic waterways. Coastal artillery reached its peak of development in the first quarter of the 20th century, when important harbours and naval bases were protected by fixed or mobile artillery that was capable of firing high-explosive shells at enemy ships far out to sea with a fair degree of accuracy. Big coastal guns were protected from enemy fire by emplacement behind thick earth-and-concrete fortifications that were equipped with underground storage rooms and electrical systems. Complicated mechanisms were installed to raise the guns above ground long enough to fire; the huge gun tubes were then quickly retracted into their concealed and well-protected pits. The largest guns used in coastal defenses were generally of 16-inch diameter.

Coastal artillery played only a minor role in World War I, however, and in the following two decades it became apparent that coastal batteries were an easy target for air and ground forces and could also be bypassed altogether. By the end of World War II fixed coastal artillery had become obsolete, and its function was eventually taken over by mobile surface-to-surface missiles.