Book excerpt: Outdoor writer Tim Renken of the St. Louis Post-Dispatch correctly predicted that Illinois Hiking and Backpacking Trails by Walter G. Zyznieuski and George S. Zyznieuski would "become the definitive trail guide for Illinois hikers". Now the brothers Zyznieuski have teamed up again and, following the same procedures that produced their classic hiking guide, have produced the definitive guide for the rapidly growing sport of mountain biking. The Zyznieuskis tell you all you need to know about mountain biking in Illinois. They note that mountain bike trails exist throughout the state, particularly in the Chicago metropolitan area. The forty-eight trails they explored for this book run from three to seventy-eight miles long (the Hennepin Canal State Trail) and range in difficulty from extremely easy to challenging. Along with a map and a complete description of each trail, this illustrated book is packed with practical information. The brothers discuss the various surfaces: dirt, mowed grass, limestone screenings, and old railroad beds. And they advise riders as to what they need to take on the trip, stressing safety necessities such as a helmet. The appendixes discuss the Grand Illinois Trail, provide information on where to order maps, and list mountain bike clubs, trail organizations, International Mountain Bicycle Association rules of the trail, and Illinois bike rules. As they did with Illinois Hiking and Backpacking Trails, Walter and George have explored every trail they mention in this illustrated guide.