During the night of April 25 to April 26, 1851, a disastrous fire again destroyed almost the whole town. The reason for it has never been discovered. The great fires spread to almost 100 houses including the Town Hall, the County Court, the Main Salt Office, the Pension Office, the Church, and several gates and towers except the Upper Tower. Just as in 1704, Traunstein was again rebuilt within a few years. It was presumed the fire was an act of revenge by the angry Haslachers. There were feelings of rage because the parochial seat was taken away from Haslach and was given to Traunstein. Later rumours came up that the carelessness of a resident had caused the fire. However, there was no evidence to support that idea and therefore the person could not be sentenced.