Complex sentence: The Wipkingen Tunnel is now one of three different routes from Oerlikon to Hauptbahnhof, each of which tunnels through the intermediate ridge and emerge from adjacent portals to the south of Oerlikon station.
Split into simpler sentences: The Wipkingen Tunnel is now one of three different routes from Oerlikon to Hauptbahnhof, each of which tunnels through the intermediate ridge. All three tunnels emerge from adjacent portals to the south of Oerlikon station.