The construction of an S-Bahn line from the Ohlsdorf station was for connecting Hamburg Airport in Fuhlsbüttel to the rapid transit rail network and, therefore for improving the airport's links with the public transportation system. The idea on its completion was for the airport to be reached from Hamburg Central Station at 10-minute intervals and with a 23-minute journey time.
The two single-track tunnels each of 1,750 meters in length were driven at a depth of 30 meters by a Mixshield named "SOFIA" (abreviation for German "Light rail Ohlsdorf - Airport under construction"). The tunnels were lined with reinforced concrete segments 0.4 meters thick and 1.50 meters long. Over 16,000 prefabricated parts each weighing up to 5 tonnes were installed in the two tunnels. The first tunnel was shell-finished after ten months work at the end of September 2005 - the second one followed after seven months work at the end of July 2006. Despite the changeable nature of the geology in the Alster valley, the tunnelling team advanced some 12.5 meters per day on average.