Carnmenellis Hill itself is three miles south of Redruth and one of just five hills in the county accorded, by virtue of height and relative elevation, the status of a 'Marilyn' (the others being Brown Willy (1,378 feet), Kit Hill (1,096 feet), Hensbarrow Beacon (1,024 feet) and Watch Croft (827 feet).
Carnmenellis has been designated as 'national character area 155' by Natural England.
- Location map: 50°10’52"N, 5°13’37"W
The hills are an upthrust of granite, similar to those of Bodmin Moor and Penwith: Carnmenelis is believed to be part of a vast 'Cornubian Batholith': a vast irruption of granite underlying Devon and Cornwall and surfacing as Dartmoor, Bodmin Moor, Carnmenellis, Penwith and the Isles of Scilly amongst other showings.
The term 'Carnmenellis Granite' refers to the granite plateau of high ground in this area.
The summit of Carnmenellis Hill (SW695364) reaches 828 feet above sea level. A microwave transmitting and receiving tower on the summit is used for telephone and computer connections as well as other data and television and radio broadcasting links.
A number of Iron Age fortifications surround the hill, but little archaeological research has been done on the site.
There is no public right of way across the summit, and the surrounding land is private farmland, though about half of the fields are Open Access land.
Carnmenellis was also the name of a former 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.
- NCA 155: Carnmenellis - Key Facts & Data at www.naturalengland.org.uk. Accessed on 8 Sep 2013
- Ghosh, P. K. (1934). "The Carnmenellis Granite: its petrology, metamorphism and tectonics". Quarterly Journal of the Geological Society 90: 240. doi:10.1144/GSL.JGS.1934.090.01-04.09.
- Charoy, B. (1986). "The Genesis of the Cornubian Batholith (South-West England): the example of the Carnmenellis Pluton". J. Petrology 27 (3): 571–604. doi:10.1093/petrology/27.3.571. http://petrology.oxfordjournals.org/content/27/3/571.abstract.
- Information on Carnmenellis from GENUKI