Imola is a city and comune in the Metropolitan City of Bologna, located on the river Santerno, in the Emilia-Romagna region of northern Italy. The city is traditionally considered the western entrance to the historical region Romagna. The city is best-known as the home of the Autodromo Enzo e Dino Ferrari which hosts the Formula One Emilia Romagna Grand Prix and formerly hosted the San Marino Grand Prix, named after the independent nation of San Marino around 100 km to the south.