The Shaw Country park is accessible by boat or by land (many people tour the San Juan Islands by bike). I've only ever visited by kayak or canoe. Just across the Channel from Lopez, the park located in Indian Cover makes a great stopping point between Odlin or Spencer's Spit and Turn Island/Friday Harbor. The beach become mud flats as the tide goes out so be careful not to get beached. As the water comes back in over warn sand it heats up making for some of the warmest swimming you'll find in the San Juan Islands.
The campground follows a road above the beach and has a good number of spread out campsites. There are composting toilets and water available. Shaw Island itself is the smallest of the ferry served islands in the area which makes it much quieter than neighboring bigger islands.
Quiet campground with beautiful views of the sound. Sitting on the beach and watching the ferries at night is a treat.