Frequently asked questions
How can I rent or buy accommodation in HafenCity? How green is the district? And what are the responsibilities of HafenCity Hamburg GmbH? Answers to frequently asked questions
Mobility
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Why doesn’t the U4 line have any overground sections?
Before the final route of the new U4 underground line was decided, alternatives with an overground layout were also analyzed. There were important arguments against realizing the above-ground version.
A flying junction, double the height of the present railroad on stilts, would have had to have been built between Rödingsmarkt and Baumwall stations. A third rail track would also have been needed, which would have forced the demolition of the historic Rödingsmarkt station. At Kaispeicher A, the site of the future Elbphilharmonie Concert Hall, the track would have had to have been furnished with expensive protection against impact with ships - which would have caused huge disruptions to ship traffic, not to mention considerable risks.
The significance of the U4 line for the transport network also had to be considered: even now when large events take place in the vicinity of the port there are severe bottlenecks on the U3 line. An above-ground line, partially following the same route as the U3, would have made the situation even worse. The solution chosen, however, also creates additional capacity.
There were also financial constraints against an above-ground line; it would have cost at least as much as the underground solution that was finally chosen (EUR 323 m). On top of this, there would have been expensive noise-proofing measures and damages payments to make outside HafenCity and in the area of the Hanseatic Trade Center.
In addition, the presence of a train track on stilts would have depressed the value of many plots in HafenCity and swallowed up many construction sites. Revenue from the sale of those plots is needed to finance other infrastructure in HafenCity, such as roads, bridges, parks, squares and promenades. Thus, if the U4 line had been run above-ground into and through HafenCity, the construction costs alone would have put a heavy burden on the special assets budget.
In other words, there are good urban planning, infrastructural and economic reasons for choosing the version of a direct, efficient underground link between HafenCity and the inner city.







