One of the quieter anchorages in the Gulf Islands National Park is James Bay on Prevost Island. I expect this is partly due to it being one of the least developed areas of the park. It may be the somewhat exposed anchorage as well, with northerly blows sending waves rolling down the bay. That said, we have always really enjoyed our times there.
For kayakers and smaller boats there is a side bay behind a reef with a beach and campground. This campground has a fantastic views looking north up Trincomali Channel. Part of the campground is in an old orchard with apples, plums and pears still growing strongly. Perhaps a good place to restock your food locker on extended voyages?
The head of the bay shallows very quickly, so while smaller boats can anchor there one does have to watch the depth closely. In general James Bay is a deep anchorage, we were anchored in 18 metres the other night.
During the summer this is a prime sunset location, a worthwhile stop on your boating holiday.