Jesi is a comune in the province of Ancona, in the Italian region of Marche. It is an important industrial and artistic center in the floodplain on the …Jesi is a comune in the province of Ancona, in the Italian region of Marche. It is an important industrial and artistic center in the floodplain on the left bank of the Esino river, 17 kilometres before its mouth on the Adriatic Sea.