<human>:  How long did the Wisconsin Glaciation last?
<bot>: The Wisconsin Glaciation started around 18,000 years ago and ended about 13,000 years ago. It was a period of extreme climate change and the glaciers grew to cover most of the state. The Wisconsin Glaciation is an example of a glacial period. Glaciers are huge sheets of ice that form when snow accumulates over many years and the weight of the snow causes the ice to grow and push into the ground. The Wisconsin Glaciation was one of the longest and most severe glacial periods in North America.