COMARCADI, a province of the Papal States, bounded on the E. by the kingdom of Naples, S. by the delegation of Frosinone and legation of Velletri, E. by the Mediterranean and the delegation of Civita Vecchia, and N. by those of Viterbo and Rieti; area, 1715 square miles. The north-eastern part of the country is occupied by the branches of the Sabine and Tuscan Apennines, among which there are many tracts of great picturesqueness and beauty. The principal summits are Monte Guadagnolo; Monte Genaro, the ancient Lucertis, 4185 feet high; and Monte San Oreste, the ancient Soracte, about 2000 feet. The principal river in the province is the Tiber, which flows from N.E. to S.W. into the Mediterranean, and it receives from the left the Teverone, anciently called the Anio. Some smaller streams flow into the sea; and there are several lakes, such as those of Albano, Bracciano, and Neri, which occupy ancient volcanic craters. The most of the country belongs to the gently-undulating tract called the Campagna di Roma, many parts of which are liable to malaria. Pop. (1856) exclusive of the city, 150,507.