According to the Book of Mormon, the hill Comnor (/ˈkoʊm.nɔːr/) was in the land Northward and was the site of a portion of the final battles of the Jaredites. The hill is mentioned only in Ether 14:28.
After a three-day battle near the seashore eastward from the plains of Agosh, the armies of Shiz retreated to the valley of Corihor and the armies of Coriantumr climbed the hill Comnor near the valley of Shurr and challenged his opponents to another battle (Ether 14:26-28).
References
Hill Comnor Wikipedia(Text) CC BY-SA