GRAVINA, a town and episcopal see of Apulia, Italy, in the province of Bari, 36 m. S.W. from Bari by rail (29 m. direct), 1,148 ft. above sea-level. Pop. (1931) 19,923 (town), 20,765 (commune). The town perhaps occupies the site of the ancient Blera, a post station on the Via Appia. The cathedral is mainly of the 15th century. The town is surrounded with walls and towers, and a castle of the emperor Frederick II. rises above the town, which later belonged to the Orsini, dukes of Gravina; just outside it are dwellings and a church (S. Michele), all of which have been hewn in the rock.