Legend "Saint Domitian and the origins of Millstatt" 
A pagan duke named Domitian is said to have lived in a castle opposite Millstatt in the 8th century. This pagan was converted to Christianity in a very strange way. 
The duke had a son who wanted to go on a trip on the lake. But because a strong wind was blowing, his parents advised him against it. Disobedient as he was, he did not let himself be dissuaded from his intention. Days passed and the son did not return. Then the message came that the ship was drifting around the lake without a soul. The dismayed father, who loved his son very much, vowed that if he found the body, he would build a church on that spot. Then he had the lake diverted into the Lieser. When the water had receded a good bit, the drowned man was found on the ledge where Millstatt is today. The father also kept his vow and became a Christian. At that time, there were a lot of idol statues around the lake. He had these thrown into the lake, but he called the place where he had the church built Mille Statuae, which means a thousand statues. Over time, this developed into the town of Millstatt. 
At the beginning of February, a service is held in honor of Domitian. A priest is said to have missed this service. As punishment, the church sank one meter into the ground, only the altar remained in place. If you want to enter the church today, you go down a few steps, but the altar is a little higher again. This duke is still venerated as a saint today, and his bones are kept in a glass coffin in a church built especially for this purpose.