Spruce Nature Trail covers a 1.25-mile loop that crosses a crystalline spring-fed creek and then touches on the muddy, glacially fed Hoh River.
More adventurous folks can head out the Hoh River Trail, an 18-mile path that ends at Blue Glacier and is used to climb Mt. Olympus. Hikers heading into the wilderness need to pick up permits at the visitors center or the Wilderness Information Center in Port Angeles [1].
Links:
[1] http://www.moon.com/destinations/washington/olympic-peninsula-and-the-coast/port-angeles