Time to play hometown tourist here.
One of the gems of Issaquah is the fish hatchery. How many fish hatcheries do you find right in the middle of a town? Not too many.
Each year Coho and Chinook Salmon return to the hatchery from early September through October. They swim from the ocean into the Puget Sound, then through three lakes (Union, Washington, and Sammamish), and up Issaquah Creek.
Because I live just down the street from the hatchery, I come visit often. It’s free, and you can take yourself through a self-guided tour.
The first weekend of October is the annual festival, Salmon Days. I have a special place in my heart for community festivals. It’s a fun time to visit the town but the hatchery is really crowded, I would suggest a week night visit if possible.