EntityQ5685749· pop 6· linked from 10 articlesHay BluffSign in to savehill (677m) in PowysConnectionstriangulation stationEntityEnglandEntityWalesEntitygeographic coordinate systemEntityWelshEntitymountain rangeEntityDevonianEntitysandstoneEntityHerefordshireEntitysummitEntityQ156150Entitytopographic prominenceEntityHay-on-WyeEntityright of responsible accessEntitymudstoneEntityescarpmentEntityOld Red SandstoneEntitybook townEntitycalicheEntityBlack MountainsEntityCategoriesBlack Mountains, WalesHills of HerefordshireMountains and hills of Powys