The ambitious hiker can set off from coast to coast (almost) on the North Country Trail from New York's Adirondacks to North Dakota, where it joins the route of Lewis and Clark. The Pacific Coast Trail, one of the toughest and most varied, "crosses the desert, winds among the tallest and oldest trees on earth, and climbs some of the highest mountains on the North American continent." The Potomac Heritage Trail offers a level and easy and uncommonly interesting 350-mile trek. Jean Craighead George, author of many fine nature-oriented books for children, fills in the background and describes the course of 14 major scenic and historic trails, with enticing asides for preview reading. Included are maps, reading lists, and a summary of biotic communities.