Ice Cellar and Bat Habitat

Before the advent of electricity, almost every castle had a sheltered cellar (here under a hill) where the ice from the nearby castle pond was piled up in the winter.
In the shade of the trees and embedded in the cool ground, the ice melted very slowly. To prevent the ingress of solar heat, there is an airlock with 2 doors and the entrance is also oriented to the north.
In this way, until the summer, people had ice to keep food cool in the castle kitchen or to serve chilled drinks.
Nowadays, everyone has an electric refrigerator and ice cellars have lost their original purpose. This ice cellar is now a hibernation place for bats.
Because it is so well insulated, it never freezes inside. It is also always damp and
cool. Two doors keep the freezing cold out and ensure the necessary peace during hibernation. In this ice cellar, 4 species are found in the winter: Daubenton's bat, whiskered bat, fringed bat and common long-eared bat.
Bats do not usually hang freely from the ceiling here during the winter, but squeeze themselves into holes and cracks in the walls. This way, they are even more sheltered.
In the summer, these nocturnal animals look for warmer places. They then stay in hollow trees
or in the castle attic.
Source: information board on site