The Henndorf bypass lead to a noticeable relief of traffic congestion. Centrepiece of the bypass is the double lane 2,150 meters long road tunnel, which is now used by approx. 20,000 vehicles per day.
During the construction of the Vienna underground line 2 extensive dewatering works with approx. 270 wells and approx. six million pumping hours were required. An electronic monitoring and control system made the measure safe.
The longest motorway tunnel in Germany is the centrepiece of the new A 71 federal motorway from Erfurt to Schweinfurt.