Ordnance Survey in Maharees

In August/September 1841 an army of Royal Engineers, under the command of Lieutenant Edward W. Durnford, visited Maharees and Castlegregory. They used a system of triangulation to map the district on behalf of the Ordnance Survey of Ireland. Sappers’ stones or benchmarks, inscribed with a crow’s foot, measured the height of a point above sea level. A number of these sappers’ stones can still be seen locally.