"A test track for an underground maglev train is to be built in southern Germany."

True!

Just this July, the Technical University of Munich completed a test track for the "Hyperloop" high-speed maglev train. The tube for the transport capsule is 24 meters long and the capsule carried two passengers at its premiere. The train works by means of vacuum: The transport capsules float in an underground, nearly airless tube without friction or air resistance, allowing them to travel at speeds of approximately 1,100 km/h.