Fort Work IV

The Fort Werk IV, also called Hoofdwerk, is the largest and most important of a series of five defensible earthworks or fortifications that were built in Bussum in the second half of the 19th century to defend the Fortress Naarden. Due to the improvement of the artillery, especially the range of the artillery, the Fortress Naarden had to be defended at a greater distance. Between 1867 and 1870, the Offensive for Naarden was built for this reason. The fortifications shielded the high area south of the Fortress Naarden, but were in front of the inundations of the water line. From here, offensive actions against the invading armies were possible. In the first phase of the battle, the field army was in front of the inundations, but in the event of a setback, the army withdrew behind the inundations. The row of forts protected the space up to Naarden, giving the troops time to retreat safely. The total expenditure for the Offensive amounted to one and a half million guilders.

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