CALAHORRA (anc. CALAGURRIS), a city of north Spain, province of Logrofio; on the Bilbao-Saragossa railway and a branch line to Arnedo. Pop. (193o) 12,004. Calahorra is built on a hill slope rising from the left bank of the river Cidacos, which enters the Ebro, 3m. east. It is the market for the grain, wine, oil, vegetables and fruit of the fertile Ebro valley, which it overlooks, and makes jam and artificial manures. The cathedral, dating probably from the foundation of the see of Calahorra in the 5th century, was restored in 1485, and subsequently so much altered that little of the original Gothic structure survives. The Casa Santa, annually visited by many thousands of pilgrims on Aug. 31, is said to contain the bodies of the martyrs Emeterius and Cele donius, who were beheaded in the 3rd or 4th century.
Calagurris became famous in Roman times for its heroic resis tance to Pompey in 76 B.C. Hunger had reduced its garrison to cannibalism before they surrendered four years later to Pompey's legate, Afranius. Under Augustus (31 B.C.-A.D. 14) Calagurris received the privileges of Roman citizenship, and later it was given the additional name of Nassica to distinguish it from the neighbouring town of Calagurris Fibularensis, the exact site of which is uncertain. The rhetorician, Quintilian, was born at Cala gurris Nassica about A.D. 35. The chief Roman remains are the ruins of an aqueduct and an amphitheatre.