State Route 18 will close for four days over Tiger Mountain for a widening project.
From 9 p.m. Thursday, Oct. 16, to 5 a.m. Monday, Oct. 20, no eastbound or westbound SR 18 traffic will be allowed between Issaquah-Hobart Road and I-90.
When SR 18 reopens, the highway will be two lanes in each direction for more than 2 miles south of I-90…