Hoorn underground tunnel dates back 450 years
Underground passages dating from before 1563 were discovered in the city of Hoorn last week. The discovery was made after heavy rainfall caused a hole in the pavement of a dead end alley. Experts are assessing whether the passage can be made accessible to the public, but it remains closed for now. Archaeologists descended down the hole and discovered a long brick tunnel. The tunnel appears to be part of a large covered sewer system that is collapsed almost everywhere, but remains intact at this specific spot. It runs beneath an old hospital from 1563 and thus dates almost certainly from that time.
Municipal sewer inspectors also entered the tunnel. It was very dark and very humid in the tunnel. One side of the tunnel appeared to be partly collapsed. On the side of the Kerkplein, the tunnel continues for some way. After a lot of water was pumped out, the inspectors could enter the part of the tunnel underneath the Sint Jans Gasthuis, the current Art Center De Boterhal on the Kerkplein. The masonry was found still completely intact. The brick corridors are partially collapsed, but a considerable distance of them remain intact. These are under the Boterhal monument. The municipality of Hoorn along with the owner of the monument, Association Hendrik de Keyser, will investigate whether the tunnel can be maintained and can be made accessible to the public. Problems with groundwater, stability and security play a role here.