The Juan De Fuca Marine trail was created to be about a one day strenuous hike.  You can also take your time and make it a two day or multi-day event and camp out.  There are shorter trails along the beaches if you do not wish to do that much hiking.  Also, there are four different trail-heads and so you get to choose the simple hikes, the challenging rocky terrain hikes, or the rigorous and multi- faceted longer hikes.   The choice is yours, but they have so much to see and do.  There are waterfalls  and tide pools, and old forests with dense growth, and strict rules to follow so that when you leave, the beauty remains.