Colli del Tronto ("Tronto's hills") is a comune (municipality) in the Province of Ascoli Piceno in the Italian region Marche, located about 80 kilometres (50 mi) south of Ancona and about 14 kilometres (9 mi) northeast of Ascoli Piceno. As of 31 December 2004, it had a population of 3,290 and an area of 5.9 square kilometres (2.3 sq mi).[3]