What’s going on UNDER Capitol Hill?

Workers are wrapping up production of more than 36,000 segments for the University Link tunnel in Seattle. Each tunnel ring is made of six precast concrete segments that each weigh 4,000 to 6,000 pounds. The rings are being connected to line the light rail tunnels. (segments are made at Traylor Technopref Precast plant in Tacoma.)

Check out this cool video showing how it's done!