Sonsonate, city in El Salvador and capital of the department of Sonsonate. Sonsonate is situated 56 km (35 mi) from the city of San Salvador and is 19 km (12 mi) from the port of Acajutla, from which it derives its commercial importance. The center of a rich agricultural area, Sonsonate is one of the oldest cities in El Salvador and retains much of its colonial atmosphere. Population (1992) 76,200.