Pampus (Dutch pronunciation: [ˈpɑmpʏs]) is an artificial island and late 19th-century sea fort located in the IJmeer near Amsterdam.

Work commenced in 1887 and creating the island and fort required the sinking of 3,800 piles and the importation of 45 thousand cubic metres of sand.

On the ground floor were the troops' quarters, kitchen, laundry, two coal-fired steam engines of 20 hp, two dynamos, telegraph, first aid station, and magazines.

[citation needed] Pampus had facilities for a permanent garrison of 200 men, but the only time it achieved that strength was during the First World War.

At this point Pampus lost its strategic role and on 15 July 1933 the military abandoned it, after having removed the anti-aircraft guns.

[citation needed] During World War II, the German occupation forces removed the Krupp guns, cupolas, and other metal to use for scrap steel.

[citation needed] In the bitter winter of 1944, the people of Amsterdam walked across the ice to salvage the wood in the fort to burn for warmth.

[citation needed] There were some plans in 1951 to site an anti-aircraft battery there, but on 9 October 1952 the fort was declared surplus and was transferred to the civilian authorities for disposal.

[citation needed] There is still one gun at Pampus, an 88 mm (3.5 in) from a German minesweeper that was wrecked during storm in 1917 north of the island of Terschelling.

Many years after the vessel's loss, dredging fortuitously recovered the gun, which ended up being donated to the Pampus Foundation.

It is open to the public from April to October, Tuesday to Sunday; €17.50 admission includes both fort and round-trip ferry from Muiden.