By the sea, Yorkshire

Spurn Head, below, is a 5km-long sand and shingle spit which extends from the north across the mouth of the Humber estuary.

Further north, the Holderness coast is formed of low cliffs made of soft glacial boulder-clay, and is subjected to severe north-easterly storms in winter. As a result, this is the fastest- eroding coast in Britain, at around 2m per year. Waves move gravel and sand eroded from the Holderness cliffs southward along the coast by a process called longshore drift (see diagram); some of this material is being deposited to build up the Spurn Head spit. On the inshore side of the spit, finer sand and mud have been deposited in the sheltered water.