During the last glacial maximum, sea level was around 600 feet lower than today. Southeast Britain was connected to Europe by a land bridge called Doggerland, which is derived from the Dogger Banks which the name of the submerged area. Northern and western Britain was covered by an ice sheet at this time. Doggerland provided a habitat for neolithic tribes migrating from the ice sheet. It was covered with forests and wetlands and was likely a prime area for hunting and gathering. About 8,150 years ago, when most of Doggerland had been inundated by the melting of the ice cap, there was a massive tsunami caused by the collapses of parts of the continental shelf off the coast of Norway. The tsunami was estimated to be 25 meters (82 feet) high. It would have devastated British coastal areas and much of the remaining area of Doggerland. There is evidence that some areas of Doggerland, which would have been islands at the time, were high enough to be refuges for the neolithic peoples in the area. These refugees may have been critical in the resettlement of Britain as sea level stabilized and the ice sheet disappeared.
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