As an employee of the Boeing Company and a lifetime member, that should have been one of my recommendations. If you have a free weekday Boeing has tours of the Everett plant where 747’s, 767’s, and 777’s are built. Plus it’s all inside the world’s largest building (in cubic feet). The tour is very popular and tickets sell out early each day.
I third the underground tour. it’s a riot. I second the Troll. The Museum (SAM) is pretty good, too, and the zoo is pretty decent. Archie McPhee, although it’s not what it used to be.
(While in Atlanta I went to the Atlanta underground with a pal, hopinh/ expecting it would be like Seattle’s. So sad.)
Be sure to make an effort to at least see Mount Rainier. Better yet, pay it a visit so you can see the Mountain up close and personal. Paradise or Sunrise, both outstanding destinations and neither is too after Labor Day. Snows are variable: they could come anytime, but usually Sept. is a nice month to go there.
Mt Rainer!
San Juans!
Puyallup fair (if you are going the first 3 wks of Sept)