Subglacial lakes are bodies of water located beneath ice sheets and glaciers. They form when pressure from the overlying ice causes the melting of ice at the base, creating a liquid environment. These lakes can vary in size and depth and are often connected by a network of subglacial rivers. One of the most studied subglacial lakes is Lake Vostok in Antarctica, which is one of the largest. Scientists are interested in these lakes because they may contain unique ecosystems and provide insights into climate change and the history of the Earth's ice sheets.