The Old Croton Aqueduct, New York City’s original water supply, carried water 41 miles by gravity from Croton-on-Hudson into the Bronx and Manhattan, passing through Sleepy Hollow and Tarrytown. Now a National Historic Landmark, the aqueduct is a horseshoe-shaped brick tunnel 8.5 feet high by 7.5 feet wide. Don’t miss this rare chance to enter one of the historic water diversion chambers along the route and see the tunnel itself.

This is a free, easy, 2-hour tour operated by Friends of the Old Croton Aqueduct. Meet at the front (upper level/south side) of the Joseph Caputo Center, 95 Broadway, Ossining, NY 10562, just west of Rte. 9/Highland Ave. at the junction of Croton Ave. (Rte. 133) — a 15-minute uphill walk or short taxi ride from the Metro-North Ossining station, with parking lots nearby. After a brief walk, descend into the Ossining weir and explore the original 1842 brick water tunnel through an engaging, story-driven tour. Please note this experience is not suitable for children under 10, and all guests are asked to stay attentive and respectful so as not to disrupt the group. Pre-registration is required, and the walk may be rescheduled if weather doesn’t cooperate.