Great Sugar Loaf
Encyclopedia
Often simply known as the Sugar Loaf ( also Beannach Mhór), this mountain is located in the east of County Wicklow
, in Ireland
, south of Bray
and to the north of the Glen of the Downs
Nature Reserve
. It is also known as the Big Sugar Loaf, to distinguish it from the Little Sugar Loaf
to the east on the other side of the N11 dual carriageway
from Dublin to Wicklow
.
Though only 501 metres (1,644 ft) high, its isolation from other hills, steep slopes and volcanic appearance makes it appear much taller than it is. Due to its height relative to the surrounding landscape the mountain qualifies as a Marilyn
.
The Great Sugar Loaf is composed of Cambrian
quartzite
, in contrast to the rounded mountains to the west, which are made of Devonian
granite
. Popularly mistaken for a volcano, it is in fact an erosion-resistant metamorphosed sedimentary deposit from the deep sea.
County Wicklow
County Wicklow is a county in Ireland. It is part of the Mid-East Region and is also located in the province of Leinster. It is named after the town of Wicklow, which derives from the Old Norse name Víkingalág or Wykynlo. Wicklow County Council is the local authority for the county...
, in Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
, south of Bray
Bray
Bray is a town in north County Wicklow, Ireland. It is a busy urban centre and seaside resort, with a population of 31,901 making it the fourth largest in Ireland as of the 2006 census...
and to the north of the Glen of the Downs
Glen of the Downs
The Glen of the Downs is a 2 km long wooded glacial valley with steep sides rising to almost 250m on the east coast of Ireland. It contains a designated Nature Reserve comprising 59 ha, as well as a candidate Special Area of Conservation ....
Nature Reserve
Nature reserve
A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...
. It is also known as the Big Sugar Loaf, to distinguish it from the Little Sugar Loaf
Little Sugar Loaf
Little Sugar Loaf, also called Giltspur Mountain , is a hill in County Wicklow, Ireland. It is situated East-North-East of the Great Sugar Loaf, separated from it by the N11 dual carriageway...
to the east on the other side of the N11 dual carriageway
Dual carriageway
A dual carriageway is a class of highway with two carriageways for traffic travelling in opposite directions separated by a central reservation...
from Dublin to Wicklow
Wicklow
Wicklow) is the county town of County Wicklow in Ireland. Located south of Dublin on the east coast of the island, it has a population of 10,070 according to the 2006 census. The town is situated to the east of the N11 route between Dublin and Wexford. Wicklow is also connected to the rail...
.
Though only 501 metres (1,644 ft) high, its isolation from other hills, steep slopes and volcanic appearance makes it appear much taller than it is. Due to its height relative to the surrounding landscape the mountain qualifies as a Marilyn
Marilyn (hill)
A Marilyn is a mountain or hill in the United Kingdom, Republic of Ireland or Isle of Man with a relative height of at least 150 metres , regardless of absolute height or other merit...
.
The Great Sugar Loaf is composed of Cambrian
Cambrian
The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...
quartzite
Quartzite
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...
, in contrast to the rounded mountains to the west, which are made of Devonian
Devonian
The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...
granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
. Popularly mistaken for a volcano, it is in fact an erosion-resistant metamorphosed sedimentary deposit from the deep sea.