Fort Saulsbury was a United States Army coastal defense fort near Slaughter Beach and Milford, Delaware. From 1924 to 1943 it was the primary heavy gun defense in the Harbor Defenses of the Delaware. In 1943 it was itself superseded by the longer-range 16-inch guns of Fort Miles at Cape Henlopen, Delaware, to which two of Fort Saulsbury's four guns were relocated. Fort Saulsbury was named for Willard Saulsbury Sr., a former US Senator from Delaware.