Beringia is a loosely defined region surrounding the Bering Strait, the Chukchi Sea, and the Bering Sea. It includes parts of Chukotka and Kamchatka in Russia as well as Alaska in the United States. The area includes land lying on the North American plate, and Siberian land east of the Siberian Chersky Range. In historical contexts it also includes the Bering land bridge, an ancient land bridge that was up to wide at its greatest extent and which covered an area as large as British Columbia and Alberta together . This land bridge connected Asia and North America at various times during the Pleistocene ice ages.