Olympic is my favorite National Park (of 20 visited). The beaches are the best feature in my opinion, there are two access points, one a road to the beach, the other a moderate hike (about 2 miles or so I think). Once on the beach you can hike for miles up and down the coast in realtive solitude (once a mile or so away from the road) with huge rocks, cliffs, crashing surf. You need a tide table and map though because there are places where you have to time it right so the tide doesn't trap you against the cliffs, it is a little dangerous (they also warn about logs getting thrown out of the surf). Best for overnight camping if you are into backpacking, but if you get an early start a good day hike is also possible.