An uninhabited islet in the Firth of Forth, Inchmickery extends to approx. 1.3 ha (3.2 acres) and lies 1¼ miles (2 km) northeast of Cramond Island, 1½ miles (2.5 km) southeast of Inchcolm and 2½ miles (4 km) northwest of Granton. The island was heavily fortified during both World Wars, part of a series of defences protecting the Firth of Forth and the naval base at Rosyth. Gun batteries and searchlights were installed in 1915 but removed by 1924. The guns were restored in 1939, with further embellishments including lookout posts, generators and an accommodation camp. Many of these military structures remain today, although they were abandoned even before World War II was over, as the threat to the Forth declined. In profile, the island looks like a battleship at anchor and it has been suggested that this was deliberately used to provide a decoy for enemy submarines.
The island is now owned by the Royal Society for the Protection of Birds (RSPB) and a reserve was established to protect its breeding terns, comprising 10-20 pairs of the rare Roseate Terns and over 400-600 pairs of Sandwich Terns.
Scenes for the film Complicity (2000) were shot here.