McLennan Reservation is a nature reserve spanning the Berkshire towns of Otis and Tyringham, Massachusetts, beside Ashintully Gardens. Owned by The Trustees of Reservations, it was protected through a series of endowments beginning in 1977 to preserve the land as open space. A 2.4-mile Round Mountain Trail loops around the reservation and serves as the main route through the property. The reservation remains part of The Trustees’ network of conserved landscapes in western Massachusetts.