This natural area is a King County Park and a wonderful gem. I visited on a Saturday afternoon. The parking area was nearly full, but the park still felt empty. The gravel road has several potholes, but most can be avoided, so drive slowly.
It was my first time at this park. From the kiosk with the map, turn right to enter the park. I walked the main loop and took my time. I saw several critters including butterflies, a garter snake, a bat, and even bears playing down by the lake.
The mosquitos are already out, so if you plan to stop for any amount of time be prepared with some bug spray. Otherwise, just keep moving.