The Cathedral of Sigüenza (Catedral de Santa María de Sigüenza) is the seat of the bishop of Sigüenza, in Guadalajara, Spain.
The Cathedral of Sigüenza (Catedral de Santa María de Sigüenza) is built in Romanesque and Gothic style.
The cathedral has its origin in 1121 when Bishop Don Bernardo de Agén (1121–1152) was named bishop by Bernard de Sedirac, Archbishop of Toledo, with the objective of reducing the influence of the bishop of Osma, at the time of the reign of Doña Urraca, daughter of Alfonso VI. Don Bernardo conquered the city 1124. In 1138 Alfonso VII donated land, and in 1144 Don Bernardo founded the cathedral, possibly on the foundations of an existing Visigoth or Mozarabic church.