In the city of Lübeck two traffic arteries regularly caused traffic jams. The problem with the heavily frequented national road B104 and the Trave waterway was that once the dilapidated bridge over the river Trave was opened, vehicle traffic broke down. The Hanseatic City of Lübeck's dream was to have a tunnel to prevent such interruptions to traffic once and for all. The federal government, however, only had the financial means for a new bridge structure. For the additional costs of a tunnel, an alternative financing source was found: public-private partnership. Under this business model, private investors realized the project in a partnership with the city of Lübeck as concession grantor. This type of cooperation was made possible in Germany by the Private Financing of Highway Construction Act which was passed in 1994 and sets the legal framework for the expansion of long-distance roads by private partners.

The Herren Tunnel was opened to traffic in August 2005. Herrentunnel Lübeck GmbH & Co. KG (HLKG) financed, built and now operates the new tunnel as private investor. HLKG is a partnership between HOCHTIEF and one further partner, each with equal shares. It is responsible for traffic running smoothly, as well as for the general servicing and maintenance of systems and installations. The tunnel will remain fully operational over the entire 30 year concession period. For its services, HLKG receives the toll charges paid by tunnel users. In this way, the cost difference between the construction of a bascule bridge and a tunnel is compensated. After the end of the concession period in 2035, the tunnel will be handed over to the city of Lübeck free of defects.