Terlago (German: Terlach) was a comune (municipality) in Trentino in the northern Italian region Trentino-Alto Adige/Südtirol, located about 6 kilometres (4 mi) northwest of Trento. As of 31 December 2004, it had a population of 1,571 and an area of 37.0 square kilometres (14.3 sq mi). It was merged with Padergnone and Vezzano on January 1, 2016, to form a new municipality, Vallelaghi.