Mud Masters Haarlemmermeer 12-14 June 2026 Haarlemmermeer (near Nijmegen) / Netherlands Visit Event Website → About This Event Location Haarlemmermeer (near Nijmegen) Country Netherlands Date 12-14 June 2026 Why This Event Military-themed obstacle race with 20+ challenges including water crossings, rope climbs, and deep mud pits across varied terrain More Runs in Netherlands View all runs in Netherlands