Apart from the numerous hollow ways across the common and the areas of diggings, the next most frequent feature are the numerous slit trenches which can be seen in groups in areas, especially around Felday. Slit trenches are zigzag depressions in the ground, which were generally back-filled after use, and may also have other associated depressions for the storage of arms etc. The extent and coverage of the surviving slit trenches, weapons trenches and dugouts suggest intensive military use.
In Felday enclosure, a prisoner-of-war camp for civilian internments was erected, traces of which evidently survive in the undergrowth. It may be a coincidence but the greatest concentration of slit trenches occurs in this locality. There are also, on the steep slopes overlooking Felday Glade, small elliptical depressions with banks on the downslope side which could be defensive positions, possibly for the Home Guard. A small rifle range is also positioned on this side of the common.