Outdoor activities. . . on land and water; Bicycle Touring in the Western United States, by Karen and Gary Hawkins. New York: Pantheon Books. 389 pp. $9.95 (paperback).

Timberline Country, The Sierra High Route, a Sierra Club Totebook, by Steve Roper. San Francisco: Sierra Club Books. 288 pp. $9.95. Hiking the North Cascades, A Sierra Club Totebook, by Fred T. Darvill Jr. San Francisco: Sierra Club Books. 365 pp. $9.95.

Karen and Gary Hawkins are on the road again with a complete guide to biking in the Western United States, patterned after their superb touring guide for Europe. Here's everything you'll need to gear up for a long-distance pedal in the wide-open West. The Hawkinses give expert suggestions for everything from selecting a water bottle to coping with the rigors of hours in a saddle. There's information about the geography, road conditions, and weather in 11 states. But perhaps best of all is the collection of 23 suggested bicycle tours, including detailed maps and descriptions of towns and sights along the routes.

To backpackers, every ounce counts. That's one reason pocket-size Sierra Club Totebooks are popular. These compact guidebooks are sturdy and stuffed full of useful maps and information. And now, two new titles have been added to the existing collection for other areas of the US and Europe.

Timberline Country, The Sierra High Route offers hikers an alternative to the popular John Muir Trail. Mountaineer Steve Roper spent several summers hiking every section of this wilderness route. The book includes topographical maps, as well as information about parks and wilderness safety.

Hiking the North Cascades is a collection of suggested hikes in the part of Washington State and southern British Columbia often called the Wilderness Alps. Each hike includes such things as estimated walking time and altitude gain.