Gromo (Bergamasque: Gróm) is a comune (municipality) in the Province of Bergamo in the Italian region of Lombardy, located about 80 kilometres (50 mi) northeast of Milan and about 35 kilometres (22 mi) northeast of Bergamo. As of 31 December 2004, it had a population of 1,246 and an area of 20.0 square kilometres (7.7 sq mi).The municipality of Gromo contains the frazioni (subdivisions, mainly villages and hamlets) Boario, Spiazzi and Ripa. Gromo borders the following municipalities: Ardesio, Gandellino, Oltressenda Alta, Valbondione, Valgoglio, Vilminore di Scalve. It is one of I Borghi più belli d'Italia ("The most beautiful villages of Italy").It is positioned within the Lombardy Prealps, specifically in the Bergamasque Prealps. It is located on the right side of the Serio River in the upper Seriana Valley; during the Middle Ages it was known as the little Toledo thanks to some smithies that turned it into an important centre for iron making and the consequent realization of cold weapons, halberds, shields and armors.