Petroglyphs -drawing of petroglyphs on the moors above Ilkley, Yorkshire. This is one of a series of three sections of a map (the other two are also in the Charles Walker Collection) of the prehistoric petroglyphs and their sites, centred on Rombald's Moor. The maps were drawn by Dr. Call (who was passionately interested in the ancient markings on the moors) in the late nineteenth century, 1800's. Collection of Manor House Museum, Ilkley.