During which epoch did significant glaciation occur?

The Pleistocene Epoch, which lasted from about 2.6 million years ago to around 11,700 years ago, is renowned for its extensive glaciation events. During this time, large ice sheets covered significant portions of North America, Europe, and Asia, leading to dramatic changes in the earth's geography and climate. These glacial periods resulted in a series of cycles of advancing and retreating ice, profoundly impacting ecosystems and the evolution of many species, including the rise of early humans.

In contrast, the Holocene Epoch is the current geological epoch that began after the last major glaciation, characterized by a warmer climate and the development of human civilizations. The Miocene and Oligocene epochs precede the Pleistocene and witnessed different ecological conditions, but they are not defined by significant glaciation in the same way as the Pleistocene. Thus, the Pleistocene Epoch is particularly notable for its glacial activity, creating a clear distinction that makes it the correct answer to this question.