The Gulf Islands National Park Reserve is of course, located on islands. This makes the accessibility a little more complicated than just driving up from Seattle or over from Vancouver.
Most people arrive courtesy of ferry and bring their car, bicycles, kayaks and other toys to explore. Arriving by float plane is another option although once you are on the islands your options will be limited as car rentals and public transportation are either in short supply or non existent.
Bring your own or a chartered boat is perhaps the best way to visit the park as many of the smaller islands are accessible by water only.