Mynydd y Garn is a
hill
A hill is a landform that extends above the surrounding terrain. It often has a distinct summit.
Terminology
The distinction between a hill and a mountain is unclear and largely subjective, but a hill is universally considered to be not a ...
in the northwest of the
Isle of Anglesey
Anglesey (; cy, (Ynys) Môn ) is an island off the north-west coast of Wales. It forms a principal area known as the Isle of Anglesey, that includes Holy Island across the narrow Cymyran Strait and some islets and skerries. Anglesey island, ...
in north
Wales
Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...
. Its high summit is crowned by a
trig point
A triangulation station, also known as a trigonometrical point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity. The nomenclature varies regionally: they a ...
and a stone
obelisk
An obelisk (; from grc, ὀβελίσκος ; diminutive of ''obelos'', " spit, nail, pointed pillar") is a tall, four-sided, narrow tapering monument which ends in a pyramid-like shape or pyramidion at the top. Originally constructed by An ...
. Erected in 1897 it commemorates Sir William Thomas, ship-owner and one time
High Sheriff of Anglesey.
Geology
The summit of the hill is formed from
Ordovician
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya.
T ...
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates ...
whilst
Gwna Group
The Gwna Group is a late Precambrian ( Ediacaran) / Cambrian lithostratigraphic group (a sequence of rock strata) in northwest Wales. The name is derived from the Afon Gwna, a river near Bodorgan on Anglesey where the strata are exposed. Thi ...
schist
Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes ...
s outcrop on its southern slopes. To their south are
New Harbour Group schists and
psammite
Psammite ( Greek: ''psammitēs'' "(made) from sand", from ''psammos'' "sand") is a general term for sandstone. It is equivalent to the Latin-derived term areniteU.S. Bureau of Mines Staff (1996) ''Dictionary of Mining, Mineral, & Related Terms.'' ...
s. Surrounding lower land is mantled by
glacial till
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is d ...
though the hill itself is free from such superficial deposits.
Access
The summit area of the hill is owned by the
National Trust
The National Trust, formally the National Trust for Places of Historic Interest or Natural Beauty, is a charity and membership organisation for heritage conservation in England, Wales and Northern Ireland. In Scotland, there is a separate and ...
and thereby open to free public access on foot. A couple of
public footpaths run across its western slopes but access to the summit is gained from a minor road to its west by a short
permissive path
In England and Wales, other than in the 12 Inner London boroughs and the City of London, the right of way is a legally protected right of the public to pass and re-pass on specific paths. The law in England and Wales differs from Scots law in ...
.
[Ordnance Survey 1:25,000 scale Explorer map 262 ''Anglesey West/Gorllewin Ynys Mon'']
References
External links
images of Mynydd y Garn on Geograph website
{{coord, 53, 24, N, 4, 30, W, display=title, region:GB_type:mountain_source:GNS-enwiki
Mountains and hills of Anglesey