Two general plans with an equal level of comprehensiveness have been created for the harbour tunnel based on two route options.
https://www.portofhelsinki.fi/en/about-us/port-of-helsinki/whats-new/general-planning-of-helsinki-harbour-tunnel-is-being-completed-greatest-differences-in-price-and-construction-start-time/
The general plan and an environmental impact assessment currently under way form a comprehensive survey based on which a decision can be made regarding the route of the tunnel.
https://www.portofhelsinki.fi/en/about-us/port-of-helsinki/whats-new/general-planning-of-helsinki-harbour-tunnel-is-being-completed-greatest-differences-in-price-and-construction-start-time/
General planning of Helsinki harbour tunnel is being completed – greatest differences in price and construction start time
www.portofhelsinki.fiThe general plan and an environmental impact assessment currently under way form a comprehensive survey based on which a decision can be made regarding the route of the tunnel.