The well was probably initially dug to a depth of 70.5 feet (21.50 meters) when the castle was built (around 1150). The lining of the well, a ring wall of several layers of large, uneven sandstone blocks, is precise masonry work carried out by a highly skilled craftsman. In a second building phase around 1650-80, the medieval well was deepened and expanded in the now lower well area. This occurred in conjunction with the expansion of the castle to a garrison. The castle garrison grew greatly in size, and more water was required. The water only flowed into the well at a depth of approx. 130 feet (40 meters) from the surface of the sandstone.
To support the construction work, the 256 foot (78 meter) long well gallery was carved into the mountain from the outside. It served to ventilate the well shaft and was intended to protect the miners from danger. For them there was a danger of poisoning from the carbon dioxide that colleted at the bottom of the shaft. However, the entrance to the gallery was located at a depth of approx. 100 feet (30 meters), which is why the ventilation was not sufficient to deepen the well further. As a result, a fire broke out in the gallery - before the entrance in the well shaft, which is the visitor's gallery today. This increased the flow of water while also enabling the deeper layers of the well to be ventilated.
After the construction work in the well shaft has been completed, the gallery was filled in and the legend of a secret passage spread. Until the German-American Fritz von Briesen picked up its trail and reopened the gallery in 1926. When the castle was partially torn down in the 1820's, the well was also filled in. However, in 1870 it was cleaned out again and used by the community of Dilsberg.