Great Herring Pond is a 376-acre (1.5 km2) warm water pond mostly located in Plymouth, Massachusetts, with the southern portion extending into Bourne. The village of Pondville in the Cedarville section of Plymouth lies on the eastern shore of the pond. The pond has an average depth of 20 ft (6 m) and a maximum depth of 42 ft (13 m). The bottom is composed of sand, rubble and muck. A tire reef was installed in 1979 toprovide additional fish shelter. The inflow comes from Little Herring Pond, and the outflow goes into the Herring River in Bourne. The Public Access Board gravel ramp in Bourne enters shallow water and is therefore best suited for canoes, inflatable and other shallow-draft, hand-carried craft.