It is linked to the southern loop of the Frederick Deep Adit. This oval-shaped shaft dates back to the early 19th century and was constructed as part of the multi-directional adit. Encased in stone and covered with a concrete slab with a ventilation grid, it is a well-preserved example of a “light hole” that also allows bats to enter the underground.

Autor: Miasto Gwarków, Lokalna Organizacja Turystyczna, 02.03.2026 r.