The area of the Reserve was originally part of the Common Waste in the parish of Llanferres. The land was enclosed in 1801 following the Kilcen and Llanferres Inclosure Act of 1794.
It eventually passed into the possession of the Colomendy Estate and remained there until it was sold in 1938. Early in the twentieth century the site was forested: mainly with Corsican Pine.
Small scale silica sand extraction was carried out on the western and south-western slopes in 1938-43 and again in 1950-3. These workings have subsequently re-vegetated naturally.
The adjacent village of Maeshafn owes its presence to the famous Maes-y-safn lead mine that runs under both it and Moel Findeg. This mine was worked from at least the early seventeenth century up to the year 1907. At least 80,000 tons of lead ore were extracted. In its most active period nearly 400 men were employed in the mine. Three steam engines, with attendant mine reservoirs, were installed in the village. The largest reservoir still exists at the western end of the Reserve and now acts as a seasonal pond. Leats, or water courses, were constructed in the late nineteenth century to feed this reservoir and can be seen in the woodland in the south western corner.