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When did the Pleistocene Epoch begin and end?

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Map showing the extent of the Laurentide, Cordilleran, and Greenland ice sheets during the Wisconsin glaciation, roughly 100,000 to 11,000 years ago. The Laurentide Ice Sheet covers most of present-day Canada and parts of the northern United States in light blue, the Cordilleran Ice Sheet covers the Pacific Northwest in teal, and the Greenland Ice Sheet is marked in purple. Modern international and state or provincial boundaries are outlined for reference. — Pleistocene Epoch Ice sheets during the Wisconsin glacial episode penetrated deep into North America.

The Pleistocene Epoch began 2,588,000 years ago and ended 11,700 years ago.1

While the definition of the epoch's lower boundary was historically subject to significant debate among geologists, the International Union of Geological Sciences and the International Commission on Stratigraphy eventually resolved the matter in 2009. They established the base of the Gelasian Stage—dated to 2,588,000 years ago—as the formal beginning of the Pleistocene. This point is associated with the Gauss-Matuyama geomagnetic reversal and serves as the base of the Quaternary Period. The epoch concluded 11,700 years ago, at which point it was followed by the Holocene Epoch.12