Otranto Cathedral (Italian: Duomo di Otranto; Basilica Cattedrale di Santa Maria Annunziata) is a Roman Catholic cathedral in the Italian city of Otranto, dedicated to the Annunciation of the Virgin Mary. It is the archiepiscopal seat of the Archdiocese of Otranto. The cathedral was consecrated in 1088. It is 54 metres long by 25 metres wide and is built on 42 monolithic granite and marble columns from unknown quarries. Its plan is a three-aisled nave with an apsidal east end. On either side of the west facade are two lancet windows.
Built on the remains of a Messapiic village, a Roman house and an early Christian church or temple, the cathedral was founded in 1068 by the Norman bishop William or Guglielmo. It is a synthesis of varied architectural styles, with Byzantine, early Christian and Romanesque elements. It was consecrated on 1 August 1088 under the papacy of pope Urban II by the papal legate Roffredo, archbishop of Benevento. The nave's partly surviving frescoes include Byzantine traces, such as the image of the Madonna and Child in the south nave and the crypt running under the apse, the sanctuary and part of the nave – dates back to the original 11th-century church – this crypt is a miniature of the famous Cistern of Theodosius or the Mosque–Cathedral of Córdoba. It has three semicircular apses and forty-eight bays interspersed with over seventy columns and pillars. It is especially marked by supporting elements from ancient and early medieval buildings. Its surviving frescoes cover a range from the Middle Ages to the sixteenth century.
The mosaic running the whole length of the nave, sanctuary and apse is 12th century in date – it was commissioned by the first Latin archbishop of the city, Gionata, and created between 1163 and 1165 by a group of artists led by Pantaleone, a Basilian monk from the monastery of San Nicola di Casole. It shows scenes from the Old Testament and chivalric cycles, as well as figures from medieval bestiaries, arranged alongside a 'tree of life', showing human experience from the Fall to salvation.