Caiatia (mod. Caiazzo), an ancient city of Campania, on the right bank of the Volturnus, 11 m. N.E. of Capua, on the road between it and Telesia. It was already in the hands of the Romans in 306 B.C., and since in the 3rd century B.C. it issued copper coins with a Latin legend it must have had the civitas sine suffragio. In the Social War it rebelled from Rome, and its territory was added to that of Capua by Sulla. In the imperial period, however, we find it once more a municipium. Caiatia has remains of Cyclopean walls, and under the Piazza del Mercato is a large Roman cistern, which still provides a good water supply. The episcopal see was founded in A.D. 966. The place is frequently confused with Calatia (q.v.).