Cape Cod (1033 km˛; called simply The Cape by Northeasterners) is an arm-shaped peninsula forming the Easternmost portion of the Commonwealth of Massachusetts, in the Northeastern United States. It is coextensive with Barnstable County. Although Cape Cod was originally connected to the mainland, the Cape Cod Canal, completed in 1914, effectively transformed Cape Cod into a large island.

Cape Cod is connected to the mainland by a pair of canal-spanning highway bridges from Bourne and Sagamore that were constructed in the 1930s, and a vertical-lift railroad bridge.