It’s impossible to see all the work happening on the SR 99 Tunnel Project from Seattle streets. So it often surprises people that major portions of the tunnel are almost complete. What you see in this photo is the cut-and-cover tunnel at the south end of the launch pit. A cut-and-cover tunnel is just what it sounds like – dig a trench, then add a roof. Later in the project, the launch pit will become part of the cut-and-cover tunnel.