Copenhagen being the capital of Denmark as well as a coastal city in the middle of a narrow strait always meant it was important to defend the city from the sea side. The placement was important because in times of war the deep water approaches to Copenhagen could quickly be mined but the mine fields would be swept in time if there were no guns to defend them hence Dragør Fort played a key role on the southern approaches. 
The fort was built during 1910 and 1915 and WWI very much accellerated work even though Denmark managed to stay neutral part of the army was mobilized to defend the country. It was built on an artificial island with an outer break water surrounding it to form almost a moat to prevent direct landing operations as well as covering the island of Amager against attempts to land troops to march on Copenhagen hence its main gun direction is South to South East but the guns were built on turntables. It covers some 32000 m2.
The outer break water forms part of the defence.
During the occupation of Denmark in World War II the position played no role and as coastal defence it was decided it was outdated but going into the Cold War it was found that the fort could play a role in a forward defence against air attacks on Copenhagen. For this leftover German material was collected and the fort was armed with light and heavy flak guns but as the U.S. military aid kicked in it was rearmed with U.S. 90 mm anti-aircraft guns however it was short lived. In 1957 the fort was disarmed air defence post due to the increased demands to missiles and rockets.
In 1984 reactivated as naval defence post to avoid Soviet vessels sneaking unseen into Danish waters. Following the end of the Cold War the old fort had no real military value and in 2000 it was final disbanded and sold to a private owner who installed a hotel and restaurant in the old barracks.
The island of Amager has now grown out to meet the fort and a marina has now formed in the shelter on the fort but its low profile to prevent easy observation can still be seen.
Playing with History 