Robert L. Wood's Olympic Mountain Trail Guide is useful for planning hikes and longer excursions. Stephen Whitney's A Field Guide to the Cascades and Olympics is an excellent trailside reference, covering more than 500 plant and animal species found in the park.
The park's newspaper, the Bugler, is a seasonal guide for activities and opportunities in Olympic National Park. You can pick these up at the visitor centers. A handy mail-order catalog of books and maps about the park is available from the Discover Your Northwest. 164 S. Jackson St., Seattle. 206/220-4140 or 877/874-6775. nwpubliclands.org.