Holland-on-Sea Cliff is a geological

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

Holland-on-Sea Holland-on-Sea is a suburb of Clacton, in the Tendring district, in east Essex in England. Located south of the little village of Great Holland and directly north of Clacton-on-Sea, it has bus links to Walton-on-the-Naze and Clacton-on-Sea. ...

, north-west of

Clacton-on-Sea Clacton-on-Sea, often simply called Clacton, is a seaside town and seaside resort, resort in the county of Essex, on the east coast of England. It is located on the Tendring Peninsula and is the largest settlement in the Tendring District, wi ...

Essex Essex ( ) is a Ceremonial counties of England, ceremonial county in the East of England, and one of the home counties. It is bordered by Cambridgeshire and Suffolk to the north, the North Sea to the east, Kent across the Thames Estuary to the ...

. It is a

Geological Conservation Review The Geological Conservation Review (GCR) is produced by the UK's Joint Nature Conservation Committee. It is designed to identify those sites of national and international importance needed to show all the key scientific elements of the geological ...

site. This site is of great importance in understanding the evolution of the

London Basin The London Basin is an elongated, roughly triangular sedimentary basin approximately long which underlies London and a large area of south east England, south eastern East Anglia and the adjacent North Sea. The basin formed as a result of compr ...

, and it is the type site for two different gravels. The "Lower Holland Gravel" was the final terrace laid down by the

River Thames The River Thames ( ), known alternatively in parts as the The Isis, River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the Longest rivers of the United Kingdom, s ...

before the river was diverted south during the Anglian glaciation around 450,000 years ago. The "Upper Thames Gravel" was deposited when the Thames was blocked by ice and not reaching the area. As the terraces can be attributed to the Anglian glaciation, they provide a fixed point for correlation other Anglian sequences in southern Britain and on the Continent. The site is a short stretch of the slope between the Esplanade and the Promenade, opposite Haven Avenue. No geology is visible.

References

{{SSSIs Essex Sites of Special Scientific Interest in Essex Geological Conservation Review sites