 In the narrow, rocky strait between it and the shore, Benedict Arnold's hastily built fleet held off the British on October 11, 1776 in the Battle of Valcour Island in what is considered the first battle in U.S. naval history.More recent military history is apparent shortly thereafter when US 9 passes now-closed Plattsburgh Air Force Base, a pillar of the regional economy Plattsburgh has struggled to replace.When it actually enters Plattsburgh, it becomes first U.S. Avenue, then Peru Street when it passes the Old Catholic Cemetery.