Lake Onota is located in Pittsfield, Massachusetts. The cottagers of the late 19th century and early 20th Century built large summer mansions along its shores. It is 617 acres (2.50 km²) and is located entirely in the City of Pittsfield and owned by it. It is divided into north and south basins due to the old roadway that marked to north end with minimal water exchange between them and empties via Onota Brook which flows southeast into the West Branch of the Housatonic River in Pittsfield. Onota is popular for fishing, swimming, water skiing, and sailing. It is also home to the famous Pittsfield event "Live on the Lake", a summer concert series consisting of local bands.