SARUM, OLD, was formerly a parliamentary borough of England, in Wiltshire, 2 miles N. of Salisbury; returning two members to parliament, though without a single house or inhabitant. It was thus, before the Reform Act of 1832, by which it was disfranchised, the most complete instance of a rotten borough. The place is, however, of great antiquity, having existed, under the name of Sorbidunum, in the time of the Romans. It was fortified by Alfred, and after the Norman Conquest was made the seat of a bishop. The cathedral was removed in 1220, in consequence of a quarrel between the bishop and the people, to Salisbury, or New Sarum; and from that time Old Sarum began to decline. Some remains of walls and ditches still exist.