Sat., May 15 Secrets of Kelly Hollow

Learn about the natural, industrial and human history of this mountain clove on a 3.5-mile hike on State trail with forest historian Michael Kudish. Space is limited, registration required. $10. Meet at State Trailhead, Mill Brook Rd., 10 a.m. Register: FMI: 845-586-4973. Rain date May 16.