Tonnetjesdelle is the largest water body on the former Noorderheide estate, lying on the transition between open heath and the Elspeterbos. Although it looks like a natural ven, it was deliberately constructed in the early 20th century as part of D.G. van Beuningen’s ambitious landscape design for Noorderheide. Built in an already marshy depression where rainwater from surrounding heath slopes collected, it was enclosed with a clay dam towards the Elspeterbos and fed by a system of ditches, ponds and pumps that linked various waterworks across the estate.