Description

The Mourne Wall was constructed between 1904 and 1922 by the Belfast Water Commissioners to define and enclose the catchment area for the newly constructed Silent Valley Reservoir. The wall is 22 miles long, 1.5m high and 0.8m thick and is constructed entirely of granite from quarries around the Mourne Mountains using classic dry stone wall techniques. It encloses 9,000 acres of mountainous terrain and is designed to keep farm animals away from the reservoirs and rivers that flow into them.