The project consists of 40 kilometres of double-track railway between Sandvika and Hønefoss, with a maximum speed of 250 km/h. Approximately 23 + 3 kilometres of this section are railway tunnels. A new station at Sundvollen, several long bridges between Sundvollen and Hønefoss will be built, as well as a new station at Hønefoss which will connect the section to the existing rail network. Around 24 kilometres of four-lane road will be built between Skaret and Hønefoss, with a speed limit of 110 km/h. The road will have a tunnel of around three kilometres, several long bridges, four stack interchanges, and will run in the same corridor as the railway between Bymoen and Styggedal. The technical focus areas on sections 3 and 5 have been the design of the station areas and motorway intersections, the long bridge over Kroksund, the huge variation in rock profiles in the tunnels under Vik, the connection of a rail section up to Hønefoss, challenging ground conditions with a great deal of quick clay, as well as the fact that construction work has to take place in areas where roads and railway lines are already in operation. The solutions for the focus areas have largely been developed through a series of well-prepared thematic meetings and the full involvement of the client in the engineering design strategy.