Description of Green Trails Maps Bonnevile Dam Green Trails, Inc founded in 1973, publishes over 140 topographic recreation map titles for the most spectacular mountain, beach desert areas North America. Including Washington and Oregon's Cascade Mountains, Washington's Olympic Peninsula, the Spring Mountains of Nevada, The parks of Phoenix and the Sky Islands of Tucson. Green Trails maps show the most current trail, road, and access information to national forests, national parks, state and local parks, and other public lands in the most clear, compact, and convenient format and scale available. Features: Original Issue 1983 Current Issue 2004 Edition 0 Scale 1:69500 Inset Scale NA Projection Lambert Conformal Conic UTM Zone 10 Datum NAD27 Sheet Size 12 x 18 Fold No Features Columbia River Gorge National Scenic Area, Bonneville Dam Visitor Center, Bridge of the Gods, State Parks and Campgrounds