Recreation and Historic Preservation. The trail runs roughly parallel to Metro North's Hudson Line from northern Yonkers to Scarborough and is accessible from numerous stations on that line. The trail briefly parallels the Rockefeller State Park Preserve and its trails. Access to the trail is easiest where it crosses Route 9, known variously as Albany Post Road, Broadway, or Highland Avenue. Heading southbound into downtown Yonkers, the trail goes on-street at Bishop William J. Walls Place and N. Broadway, where it follows the sidewalk on N. Broadway for one block, and then makes a left onto Ashburton Avenue going east. At Palisades Avenue, it makes a right and the trail bed restarts. Remnants of the aqueduct still exist and can be seen along the trail, including 21 stone ventilators, three stone weirs (chambers which were used to empty the aqueduct for maintenance), and one "Keeper's House" located in Dobbs Ferry. The Keeper's House in Dobbs Ferry was built in 1857 and is the only remaining of four Keeper's Houses that is both on the aqueduct and open to the public. The only other remaining Keeper's House is located in Ossining, but it was moved off the aqueduct, is privately owned, and is not open to visitors. A portion of the Old Croton Aqueduct, running from the Croton River to Manhattan, was listed as a National Historic Landmark in 1992. The Croton Water Supply System was also designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1975. The interior of the Old Croton Aqueduct has been explored and documented by The LTV Squad, Miru Kim and historian Steve Duncan. Gallery See also Croton Aqueduct Gate House High Bridge, New York City - part of the old Croton Aqueduct system New Croton Aqueduct List of National Historic Landmarks in New York National Register of Historic Places listings in northern Westchester County, New York National Register of Historic Places listings in southern Westchester County, New York Notes References External links NYC GOV Water System History NYC GOV New York City's Water Story "How a Massive Public Works Project Saved a Parched New York," by SAM ROBERTS, New York Times, December 4, 2017 Old Croton Aqueduct State Historic Park Friends of the Old Croton Aqueduct NYC Segment according to the NYC Department of Parks and Recreation ASCE History and Heritage of Civil Engineering - Croton Water Supply