I have lived near the locks all my life, and have always been fasinated with it. It is so much fun to just go and spend a relaxing day there watching boat traffic and the fish go through the latter, and the occassional train rolling over the nearby trainbridge. Discovery Park (Magnolia Side) and Golden Gardens Beach (Ballard Side) are very close as well. Hit up all of these places to make your day perfect.
Pros: fun, interesting, free
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