Coordinates: 50°10′52″N 5°13′37″W / 50.181°N 5.227°W
Carnmenellis Hill (or just Carnmenellis) gives its name to the area of west Cornwall in England, between Redruth, Helston and Penryn. The hill itself is situated approximately three miles (5 km) south of Redruth. It is one of five Marilyns in Cornwall; the others being Brown Willy (420 m), Kit Hill (334 m), Hensbarrow Beacon (312 m) and Watch Croft (252 m). The natural region of Carnmenellis has been designated as national character area 155 by Natural England.
Penmarth, a nearby village, is sometimes referred to locally as Carnmenellis.
The term 'Carnmenellis Granite' refers to the plateau of high ground in this area, one of five granite plutons in Cornwall that make up part of the Cornubian batholith (see also Geology of Cornwall).
Carnmenellis was also the name of a former ecclesiastical parish created in 1846 from part of Wendron parish. Initially, the parish included the area which later became the parish of Pencoys. Today, most of the Carmenellis area is in Stithians civil parish.