Campagna di Roma is the low lying region surrounding the city of Rome. It occupies about 800 square miles and is bounded on three sides by mountains and hills and to the south west by the Tyrrhenian Sea. It was a favoured residential area in Roman times but was abandoned because of the prevelance of malaria in the Middle Ages, but largely reclaimed in the late nineteenth and early twentieth centuries. See also Claudian Aqueduct. Ruskin 's description in Modern Painters is based on a diary entry for 6 June 1841 of the Campagna with the 'remains of the aqueduct overseen by the Alban Mount' ( Works, 3.43).