The Kloostermloen is a traditional polder mill located on Stadsweg in the town of Garrelsweer. The mill was built in 1877 to replace an older mill that had been destroyed in a fire. The mill was used to drain the local polder – a 584 hectare area of land. The mill was upgraded in 1921 to use an electric motor. Today, the mill is in very poor condition – some restoration work was performed in 1980, but there is still more work needed to restore the mill to working order.