Bottled water is sold in the Visitor Center. Picnic lunches are allowed and there are a number of local eating places and sources for takeaway food.
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A number of Tour Companies include the Locks. Other options are Seattle Metro buses or Urber.
If you want to experience the Locks from a boat, try Argosy Cruises.
getting to the locks w/o a car?
food and drinks at the locks?
The small locks are closed for 2 weeks in March. The large locks are closed for 2 or more weeks in November, check the News & Updates page for Army Corps Official News Releases and Facebook.