The Quarter of the Engineer
The brain behind the fort
Lieutenant Colonel E.J. Sommerfeldt of the Army Corps of Engineers designed the Garderhøjfort. He also designed another part of the land fortification, Vestvolden, the Western Rampart. The main obstacle of the Copenhagen land fortification was the inundation of the Northern Front. South of the forest area Dyrehaven a series of inundations were prepared in order to stop enemy advance towards Copenhagen from the North.
Where does the water run out?
The inundation went from the smaller forest Ermelunden over the lowland South of Dyrehaven and almost out to the sea – Øresund. The enormous amount of water was to be taken from the almost 10 square kilometres lake of Furesø – with 38 meters depth the deepest lake in Denmark. A system of canals, barrages and dams would lead the water flow to the areas to be inundated.
The Enemy should be kept away from the inundation works
It was important to secure the dams from enemy destruction and thus drain the inundation. Consequently, fortifications were constructed to prevent this, particularly Garderhøjfort and Christiansholmslinien, a strong fortification line South of Klampenborg.
The inundation was never implemented, as Denmark was not attacked. The construction of the whole system was indeed a challenge to the engineers. The experiences from all this was to the benefit of Danish industry and building construction.
It is complicated to be at war in unknown territory. Consequently, the armies depend on topographical maps with detailed information of the structure of the terrain. The General Staff of the Danish Army was deeply involved in the mapping of Denmark from the beginning of the 1800’s and forward.
Maps and contour lines
Detailed topographical maps were used to plan the inundation of the lowlands around Copenhagen. The contour lines inform about low water consuming areas, suitable places for barrages, the velocity of the water running out of Furs, and which direction the flood of water would take.
Modern map and navigation technology is of the highest importance for military operations. GPS technology was developed for military purpose, and is today accessible for everybody.