After the Allied airborne landings near Arnhem and Nijmegen, the frontline was suddenly in the extreme north of Limburg. Heavy fighting broke out, and a large group of refugees from the area sought refuge in the cellars of the villa of Baron Van Verschuer. Dozens of German soldiers did the same.

The villa, also known as the castle, did not escape the violence of war, however. The coach house took a direct hit and was badly damaged. On Thursday 28 September, everyone was ordered by the Germans to evacuate. One day later, heavy fighting broke out on the Sint Jansberg and the turret of the villa was blasted. The villa, the farms nearby, the water mill with the miller's house and other buildings were badly damaged, because the front came to a halt exactly here.

By far most of the destruction was caused in February 1945 when the Allies launched a major offensive to conquer the area between the rivers Meuse and Rhine (Operation Veritable, also known as the Battle of the Reichswald). On 27 April 1945, Father Herman Hoek from Groesbeek visited part of the battlefield on the Sint Jansberg: "Went to the Kiekberg; counted twenty dead, half decomposed soldiers. Sorrowful scene. The Baron's woods have been shot to pieces. Trenches, mines and ammunition everywhere; back in the pouring rain."