DNW, the German-Dutch Wind Tunnels, was established by the German Aerospace Center DLR and the Dutch Aerospace Center NLR.

DNW is a non-profit foundation under Dutch law, with headquarter in Marknesse in the Netherlands. Its tunnels are situated in a number of locations in the Netherlands and Germany: Marknesse, Amsterdam, Braunschweig, Göttingen and Köln.

DNW operates its own large, low-speed facility and the aeronautical wind tunnels of DLR and NLR. DNW provides solutions for the experimental simulation requirements of aerodynamic research and development projects. These projects can originate in the research community (universities, research establishments or research consortia) or in the course of industrial development of new products. Most of the industrial development projects originate in the aeronautical industry.

5 out of its 10 wind tunnels are located in Niedersachsen:

• The NWB in Braunschweig is a closed-circuit low speed wind tunnel of the atmospheric type, located on the premises of the DLR.
• The transonic wind tunnel (TWG) in Göttingen is a facility for research and development tests in the transonic and supersonic domain.
• The high-pressure wind tunnel (HDG) in Göttingen is a research and development facility for aerodynamic experiments.
• The cryogenic Rohr wind tunnel (KRG) in Göttingen is a research and development facility for aerodynamic experiments.
• The Ludwieg tube (RWG) tunnel in Göttingen is a research and development facility for aerodynamic experiments at supersonic and cold hypersonic flow.