Holderness owes its existence to the most recent (Devensian) glaciation. This began around 110,000 years ago and lasted until around 10,000 years ago. The constant depositing of water, as ice, led to a lowering of the sea level until it was 300 to 400 feet below today’s sea level. Thus Britain was not an island but linked to mainland Europe by “Doggerland” an uninhabited plain of tundra. Doggerland incorporated what is now the English Channel and most of what is now the North Sea (the exception being the Norwegian Trench, off the south west of Norway). The Rhine, together with tributaries, including the Thames, flowed into the Atlantic via the “English Channel” route while the Humber (and those rivers to its north) flowed north east across Doggerland into the Norwegian Trench.
When the ice retreated, and the land warmed, Doggerland became a fertile, undulating plain. Trees and other vegetation flourished and animals such as deer and wild boar made their way from the uplands of what is now northern mainland Europe into Doggerland. The animals were followed by mesolithic hunter-gatherers. However, the melting ice eventually caused the sea level to rise again and Doggerland was progressively submerged. For a time, the hunters could adapt to the changing conditions, by adopting fishing and boat building, but they were eventually forced to relocate, either to Britain or back to the mainland. The demise of Doggerland was hastened by a two foot rise in sea level caused by the release of meltwater from a huge North American lake and by a catastrophic tsunami (around 6200 BC) caused by an underwater landslide (the Storegga Slide) off the coast of Norway.
THE CREATION OF HOLDERNESS
The underlying geology of Holderness is cretaceous chalk, but this is buried under deep glacial deposits of boulder clays and glacial lake clays deposited during the Devensian glaciation. Before the glaciation, the Humber flowed into the North Sea at a point close to where the Humber Bridge now stands (the Humber Gap). Today, Holderness consists of material transported by the glaciers from as far afield as north east England, the Lake District, Scotland and Scandinavia.
Having deposited the material from which Holderness is formed, the eventual melting of the ice gave rise to the distinctive profile of Holderness. The meltwater formed a large lake, known as Lake Humber, blocked by ice at the Humber Gap. When the ice dam eventually melted, the pent up water flowed down the Humber but came up against a moraine near modern Salt End. This forced the river to turn in a southerly direction. This “dog leg” gave rise to the characteristic profile of the Holderness peninsula.
As the ice started to melt, some areas of ice remained frozen for longer than others. Solid glacial deposits formed around the ice and when this eventually melted, meres were formed and peat later deposited on their beds. There are also beds of sand and gravel, deposited in the late glacial period.
Thus, around 8,000 years ago, after the ice had melted, Holderness was essentially a bare, boggy plain with a scattering of meres. Over time, all the meres (or “seas”) of Holderness, except for that at Hornsea, dried up, and are now traceable only by the peat deposits that they left behind.
The Holderness boulder clays are very subject to coastal erosion and this yields up large quantities of fossils and “erratic” rocks transported by the glaciers. The rate of erosion of the 35 miles of coast between Flamborough and Spurn is such that the coastline has retreated by around 3.5 miles since Roman times, more than 30 villages being lost in the process.