High Willhays of the highest hill on nearby Bodmin Moor, and suggested that a watch for beacon fires used to be kept here. He also posited a possible link to the word "gwili" meaning winding or tortuous, but said it was unlikely this was where it originated from. "The Place-Names of Devon" (1931) notes that the peak was named "Hight Wyll" in a document of 1532, and was known in 1827 as "High Willows". The authors state that the name may simply be a compound of "high" and "well" (meaning "spring"), though they admit that the additional syllable at the end is
High Willhays England south of Ingleborough in the Yorkshire Dales, but since then surveys have shown that Kinder Scout is also higher (albeit less prominent). The geology of High Willhays, like most of Dartmoor, consists of granite intruded about 280 million years ago. However High Willhays is in an area of the northern plateau of the moor where the exposed rock has noticeably fewer of the large feldspar megacrysts that are typical of most of Dartmoor's tors. Each of the outcrops displays lamellar bedding. High Willhays is within one of Dartmoor's Danger Zones, areas used periodically by the British Army for exercises.