capital of the judicial district and diocese of the same name, in the province of Logroño, Spain, 24 miles S.E. of Logroño, N. Lat. 42° 12', W. Long. 2° 0'. It occupies an elevated site on the left bank of the river Cidacos, near its junction with the Ebro, and contains about 1320 houses, mostly mean, a cathedral in the mixed Gothic style, an episcopal palace, and several conventual and other schools. The climate is cold and damp, but the soil produces in abundance grain, pulse, flax, wine, and oil. Pop. 5994.

Calahorra is the ancient Calagurris Nasica, celebrated for its fidelity to Sertorius in his war with Pompey and Metellus; and in the suburbs may still be traced the remains of an ancient Roman circus, an aqueduct, and a nunnachia. It is said to have been the birth-place of the rhetorician Quintilian.