The B/ON-1100 is a World War I-era bunker located near Diksmuide in West Flanders, Belgium. This concrete fortification was part of the extensive defensive network constructed along the Yser Front during the First World War. Diksmuide was a strategically important town due to its position near the Yser River, which played a crucial role in the Belgian defensive strategy against German forces.
The bunker exemplifies the military engineering of the period, designed to withstand artillery bombardment and provide shelter for troops.