The flow field of the thick delta wing at high subsonic and at supersonic speeds has been the subject of quite a variety of investigations at the Technical University of Berlin. The research work started as early as in the late 60s and is still going on today. It was triggered off by the initiatives of the late 'Dietrich Kuechemann-aiming' at a hypersonic transport and it was taken as a contribution to the Eurohyp activities. The wing configurations investigated at the Technical University of Berlin were of simple shape: Delta wings with straight leading edges and triangular cross sections of different thickness. The interest was focussed on the development of the leeside flow with changes in angle of incidence and main stream Mach number. In addition to that similar delta wings with curved leading edges and also with a jump in leading edge sweep were investigated, as well as two types of wave riders. Besides some theoretical work mainly wind tunnel test were made applying available test techniques: Surface pressure measurements, Pitot measurements in the flow field, flow visualization by Schlieren, vapour and oilfilm technique, skin friction determination using oilfilm interferrogramm and, finally, laser velocimetry (laser-two-focus-system). The experimental investigations were particularly challenging, because of the small models of generally not more than 6 cm span. This limitation arose from the small size of the transonic and supersonic wind tunnel (15 x 15 cm). The paper will give a review on the activities and a brief report on some of the findings.