Tha Anacortes Marina has parking available for free for those renting slips, chartering boats, and guests of the Marina. At least one of the gates is closed every night. It is an open air lot, not a structure. Don't park along the front gate closest to the docks unless you have a permit, otherwise the rest of the spots are up for grabs.
You can park on the street nearby for free. The city of Anacortes has free parking in the downtown area and on the some of the streets around the marina you just need to look for it.
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