The landscape was changed dramatically as vast sheets of ice scoured out new valleys and flattened mountains. In that time, what is now Alaska and Siberia weren’t separated by the Bering Strait; they were connected by an area of land which has now disappeared, called Beringia. Beringia (this is the name given to this area by modern historians—we have no idea what the people who lived there called it) covered an area of more than 600,000 square miles (1,600,000 square kilometers) and stretched from the Lena River in what is now Siberia to the Mackenzie River in what is now Canada.
