Massachusetts State Parks Pet Policy: Pets on a leash no longer than 10 feet are allowed at some Massachusetts State Parks and Forests. There are specific locations where dogs are not allowed for public safety, public health, or habitat concerns or deed restriction purposes. Pets are not allowed in swimming pools; playgrounds; parking areas; cabins, yurts and the encompassing areas; Boston Harbor Islands; Walden Pond State Reservation, Concord; Moore State Park, Paxton; City Square Park, Charlestown; Plum Island’s Sandy Point State Reservation, Newburyport; and All Division of Water Supply Protection land and water. From May 1 through September 15 of each year, unless otherwise posted, dogs are not allowed on coastal beaches or in designated swimming areas of inland beaches. From April 1 through September 15 of each year, unless otherwise posted, dogs are not allowed on coastal beaches designated as priority nesting habitats for shore birds.
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