The Zurich cross-city route project was one of Switzerland’s key projects in recent decades. TBF was significantly involved in two phases. The Gessnerallee passage and city connection, the shell of the city tunnel and the new fire ventilation centre were built during construction of the new Löwenstrasse railway station. Existing buildings were demolished, groundwater lowering was performed, and diaphragm walls/diaphragm wall piles as well as micropiles/abutment supports and temporary supports for hall roof pillars were constructed. In addition, platform auxiliary bridges and track bridges were installed and removed.
During phase four, the Weinberg tunnel was connected to Oerlikon railway station. This involved the construction of the Hofwiesenstrasse/Birchstrasse retaining wall, the Birchsteg and Regensberg bridges and the subway structure.

As part of the engineering consortia, TBF was responsible for project planning and construction management to a significant degree during both phases.