Prehistoric Britain
A final ice age covered Britain between about 70,000 and 10,000 years ago. There was an extreme cold snap between 22,000 and 13,000 years ago, which may have driven humans south out of Britain again. The environment during this ice age period would have been a largely treeless tundra. It was eventually replaced by a warmer climate, perhaps reaching 17 degrees Celsius (62.6 Fahrenheit) in summer, which encouraged the expansion of birch trees as well as shrub and grasses.