 While it was located on the main road through the area, the center of Chappaqua was a mile (1.6 km) further up it, the area around the extant Quaker meetinghouse established by the settlement's founders eight decades earlier, now listed on the National Register as the Old Chappaqua Historic District.In the middle of the century the Harlem Valley Railroad, later part of the New York Central, was built along the Saw Mill River.The connection to New York changed Chappaqua's economy in two ways.