The new line from Stuttgart to Ulm is part of the new trans-European Main Line from Paris to Budapest. It crosses the Swabian Alb and is divided for planning purposes into the
sections Albvorland, Albaufstieg, Albhochfläche, Albabstieg (Alb foreland, ascent, high plain and descent) and the conversion of Ulm railway station. While the high plain of the Alb is predominantly characterised by open-air line, the sloping sections each side are dominated by long tunnels. The areas have similar geology, with karstified white Jurassic limestone being the most frequent formation. For the construction of a structurally stable and serviceable high-speed permanent way, careful handling of the karst is essential. The article in tunnel 4/2015 presents the concept for karst investigation and treatment for the Alb descent.