Rock Creek Wilderness is one of the Siuslaw’s most remote wildernesses with no developed trails or trailheads. So bring a map and compass for a real wilderness experience. Pristine rain forest canyons run with crystalline water pouring into either Rock Creek itself in the heart of the Wilderness or Big Creek on the southern boundary. Mossy big leaf maple and red alder hang suspended over both creeks as they make their way toward the salty waves of the Pacific Ocean. Look carefully for Oregon Silverspot butterflies on the tall ridge between Rock and Big Creeks; these orange-and-brown butterflies live only here and in two other places on earth.Near the coast, tremendous old-growth Sitka spruce sometimes reach nine feet in diameter, giving way to old Douglas fir farther inland. Pink-blossomed rhododendron bloom in May, joining salal, salmonberry, and sword fern in their efforts to keep the ground perpetually shaded. Salmon, steelhead, and cutthroat trout migrate up creek to spawn. Fog cools the area almost all of every summer; and winters are usually snow less.