Reservoir Park is a historic park on Boylston Street in Brookline, Massachusetts. Its principal feature is Brookline Reservoir, formerly an element of the public water supply for neighboring Boston. The reservoir was built in 1848 as the main terminus of the now-defunct Cochituate Aqueduct, which delivered water from Lake Cochituate in the western suburbs. The reservoir covers 21.1 acres (8.5 ha), and is roughly kidney-shaped. A gravel path extends around the perimeter of the reservoir. The park is bounded on the north by Boylston Street (Massachusetts Route 9), on the west by Lee Street, on the south by Dudley Street, and on the east by Warren and Walnut Streets.