Is it ensure, insure, or assure?
ancient royal forest of oak and beech in western Gloucestershire, England, covering an area of about 26,000 ac (10,500 ha) between the Rivers Severn and Wye. It became a National Forest Park administered by the Forestry Commission in 1938. Forest residents ("commoners") retain their ancient feudal rights of sheep pasturage and hold their verderers' court, a judicial anachronism, at Speech House; miners operate small private coal pits. Lydney, Coleford, and Cinderford have small industries. Roman antiquities include a road, villa, and ironworkings.