Whaleback Shell Midden is a shell midden, or dump, consisting primarily of oyster shells located on the east side of the Damariscotta River in Maine, United States. Other shell middens are located on the estuary in both Damariscotta and Newcastle. The middens in this area were formed over about 1,000 years between 200 BC to AD 1000 (By 1875 oysters that were once abundant were no longer native to New England waters.