Wine country starts in Woodinville with Chateau St. Michelle and Columbia Crest but dozens more have been added. For a longer wine tasting trip, hop over the pass toward Yakima. There are many wineries all over the state for that matter, so get a designated driver and plot out a tasting route wherever you go.
On the way to Rainier, consider going to Norwest Trek in Eatonville for a wildlife experience.
After May 1st, the Hyak tunnel is open - 2.3 miles of tunnel that long ago let the trains pass through the mountains. Bring flashlights and warm clothes.
June through August - Take a day to go to U-Pick some strawberries, raspberries, or blueberries. Our family favorite is Bybee-Nims farm at the base of Mt. Si in August for blueberries.
Take I-90 to the Columbia river, and then to north a mile to the petrified forest.
Make the Whidbey Island loop with a stops at Deception Pass and Fort Casey. Enjoy the ferry ride at the end of the loop. Take along a kite for Fort Casey, there is always wind there.