Nauset Beach was the scene of Cape Cod’s first shipwreck, the ketch Sparrowhawk, near Pochet on Dec. 17, 1626. Offshore, a German submarine attacked on July 21, 1918, shelling a tug and sinking four barges. Some shells overshot the beach and landed in the marsh and Pleasant Bay, the only shells to hit U.S. soil in World War I.