In large parts of Northern Twente rocks of Eocene age outcrop or occur below a thin cover of sand and gravel. Some new localities of these Eocene deposits, e.g. road-ditches, waterborings and buildings-pits in the Vasse-Ootmarsum and Oldenzaal-Losser areas are described in detail. Of special interest is a siltstone (Vasser siltsteen) occurring interbedded with sandy loam. Evidence for a lower Eocene age is presented. Blocks of this siltstone abundantly are found in the glacial deposits of the area.