Barberville Falls in Poestenkill, New York, is a waterfall and nature preserve on the Poesten Kill that protects 138 acres of undeveloped land. There, the creek drops about 90 feet in a fall roughly 50 feet wide before entering a broad, steep-sided gorge. Water from about 35 square miles of the Rensselaer Plateau keeps the stream flowing year-round, with its strongest flow in spring snowmelt. The site is also significant for its geology, including Rensselaer Greywacke with slate and limestone above, and for remnants of an unfinished mill project near the base of the falls.