The foundation stone of Ulm Minster was laid on June 30, 1377. In 1543 construction stopped for good, officially for reasons of cost. For three hundred years the main tower stood unfinished, at about 70 meters under an emergency roof. Restoration and completion began in 1844. In 1890 the main tower reached its full height of 161.53 meters. The builders worked from the medieval design of Matthäus Böblinger, which the architect August Beyer modified.