Freiburg Minster, German: Freiburger Münster or Münster Unserer Lieben Frau, is the cathedral of Freiburg im Breisgau, southwest Germany. The last duke of Zähringen had started the building around 1200 in romanesque style, the construction continued in 1230 in Gothic style. The minster was partly built on the foundations of an original church that had been there from the beginning of Freiburg in 1120. In the Middle Ages, Freiburg lay in the Diocese of Konstanz. In 1827 the Freiburg Minster became the seat of the newly erected Catholic Archdiocese of Freiburg and thus a cathedral.