The State Route 99 viaduct in downtown Seattle will  close from 6 a.m. Saturday (March 24) to 5 a.m.  Monday (March 26) for is semiannual inspection, according to the Washington State Department of Transportation.

The closure is between the West Seattle Bridge and the Battery Street tunnel.

The viaduct eventually will be completely torn down as part of a major project to replace it with a tunnel.