The shortest trails are the self-guiding trails 0.5 to 2 miles long. See the list under Ranger-led Activities. The valley trails that run along the base of the Teton Range and take you to the large lakes in front of the mountains are also shorter and less arduous than the mountain trails. The valley trails will pique your interest and help you decide if you wish to hike further into the mountains. You can take a half-day to all-day hike into the canyons between Teton peaks. The walking will be more difficult, requiring some up- and downhill effort, but the rewards—mountain views, wildflowers, and wildlife—are worth it. You can take multiple-day trips over highcountry passes and into the alpine zone. A free backcountry permit is required for all overnight camping. In the visitor centers you can buy the _Teton Trails_ guide booklet. It offers shaded relief trail maps, lengths and hiking estimates, scenery identification drawings, and photographs on which you can trace your route. Rangers can direct you to interesting hikes and help you assess the level of difficulty. If you plan to travel off trail you must register at Jenny Lake Ranger Station, or at the Moose Visitor Center from October through May. Overnight travel requires a free backcountry use permit (see Backcountry Basics). Wear comfortable and sturdy footgear no matter how far you hope to travel. Even on shorter hikes, be sure to carry raingear. Afternoon thundershowers are common throughout the hiking season and can occur suddenly. The day may be sunny and warm, but a quick drenching rain can spell big trouble for hikers without raingear. Life-threatening hypothermia occurs most often in the 30 to 40°F temperature range, especially if clothing is wet and there is some wind. Be prepared. Don’t take chances. You will also need to carry water on your hike. At high altitudes the sun is hot and the humidity is low; you get thirsty quickly. Microorganisms in stream water can cause intestinal problems 10-14 days after you drink, so use your canteen. (See Water Warning under Backcountry Basics.) Be sure to carry lunch and some high-energy snacks to munch on while you walk. Add sunglasses, sunscreen, a hat, and camera, and you will be prepared to enjoy your day on the trail. Please read Bear Warning under Backcountry Basics. Pets are not permitted on trails or in the backcountry. Most valley trails are open by early June. Highcountry trails may remain closed by snow until mid-July. Please note that horse parties have the right-of-way on trails. Step well off the trail and remain quiet while horses pass. Backcountry Basics