The River Cober () is a short river in west

Cornwall Cornwall (; or ) is a Ceremonial counties of England, ceremonial county in South West England. It is also one of the Celtic nations and the homeland of the Cornish people. The county is bordered by the Atlantic Ocean to the north and west, ...

, England,

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

. The river runs to the west of

Helston Helston () is a town and civil parish in Cornwall, England, United Kingdom. It is situated at the northern end of the The Lizard, Lizard Peninsula approximately east of Penzance and south-west of Falmouth, Cornwall, Falmouth.Ordnance Survey: ...

into The Loe, Cornwall's largest natural lake.

Geology and hydrology

It rises in

Nine Maidens Downs Nine Maidens Downs is a moorland southwest of Four Lanes in Cornwall, England, UK. Stone circles The name Nine Maidens comes from two Early Bronze Age stone circles which stood 18m apart on the downs. There was a belief that the stones were orig ...

, directly between Hangman's Barrow to the west and the Nine Maidens

stone circle A stone circle is a ring of megalithic standing stones. Most are found in Northwestern Europe – especially Stone circles in the British Isles and Brittany – and typically date from the Late Neolithic and Early Bronze Age, with most being ...

to the east, in the former Kerrier District and runs to the west of the town of

before entering the largest natural lake in Cornwall – Loe Pool. The water is impounded by the natural barrier, Loe Bar, and the river system can be traced several kilometres out into

Mount's Bay Mount's Bay () is a bay on the English Channel coast of Cornwall, England, stretching from the Lizard Point, Cornwall, Lizard Point to Gwennap Head. In the north of the bay, near Marazion, is St Michael's Mount; the origin of name of the bay. ...

. Mining activity of over one hundred years in the river catchment, ceased in 1938, in the

Wendron Wendron (; historically St. Wendron) is a village and civil parish in Cornwall, England, United Kingdom. It is approximately to the north of Helston and to the west of Penryn. The parish population at the 2011 census was 2,743. The electoral ...

and Porkellis mining districts; and the engine house of Castle Wary (also known as Wheal Pool), near Nansloe can still be seen on the east side of the river below Helston. The lower reaches of the river were

canalised River engineering is a discipline of civil engineering which studies human intervention in the course, characteristics, or flow of a river with the intention of producing some defined benefit. People have intervened in the natural course and b ...

in 1946 and a causeway was built over Loe Marsh in 1987.Le. Messurier, B. and Luck, L. (1998) ''Loe Pool and Mount's Bay''. No. 12 in The National Trust Coast of Cornwall series of leaflets. The meaning of the name is uncertain, but two of the earliest records are: "in 1260 we find, 'Chohor' lternately known as in non-unified , meaning 'scarlet river' due to its earlier colour from mining waste and a few years later, 'Coffar'". The present name 'Cober' is unlikely to be derived from 'Coffar', since it was known as the 'River Loe or River Looe' around four hundred years ago, in Carew's time, according to the map of Powder Hundred.

History

A common belief is that until the 13th century the River Cober ran directly to sea, until its mouth became blocked by a deposition of sand which formed

Loe Bar The Loe (), also known as Loe Pool, is the largest natural freshwater lake () in Cornwall, United Kingdom. The earliest recorded appearance of this simple name form was in 1337, when it was called "La Loo", but is mentioned as 'the lake' in 130 ...

and created Loe Pool. Loe Bar was most likely created by eustatic sea level rise after the last ice age. The rising sea level pushed a large amount of sediment into the mouth of the river, blocking it and creating a

barrier beach Barrier islands are a coastal landform, a type of dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few is ...

.May, V.J. Loe Bar. In May, V.J. and Hansom, J.D. (2003) Coastal Geomorphology of Great Britain, Geological Conservation Review Series, No. 28, Joint Nature Conservation Committee, Peterborough, 754 pp. Loe Bar consists mainly of

flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start ...

, a rock not found in Cornwall; the nearest onshore source is in east Devon, away. The most likely source of flint is found offshore; the drowned terraces of a former river that flowed between England and France and is now under the

English Channel The English Channel, also known as the Channel, is an arm of the Atlantic Ocean that separates Southern England from northern France. It links to the southern part of the North Sea by the Strait of Dover at its northeastern end. It is the busi ...

. In the 1870s, a total of £3000 was spent by the ″Porkellis-moor-adventure″ on the exploration of

china clay Kaolinite ( ; also called kaolin) is a clay mineral, with the chemical composition aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4. It is a layered silicate mineral, with one tetrahedron, tetrahedral sheet of silica () linked through oxygen ...

deposits on Porkellis Moor. A bakehouse-flue and large tanks were built, but in 1879 the adventurers sold by auction their holdings and by 1884 the works were derelict. The Helston branch railway (which closed in 1962) ran along part of the valley into Helston. The Railway line crosses the main River on the 5-arch Cober Viaduct.

References

{{authority control Helston Cober