The Champlain Valley is a large valley that extends from upstate New York to central Vermont. It is named after Lake Champlain, which fills the valley's southern end. The lake was formed by glaciers during the last ice age, and the valley was carved out by melting glaciers and rivers flowing from them. Today, the Champlain Valley is home to many farms and towns, as well as the cities of Burlington, Vermont and Plattsburgh, New York.