Backpacking is the outdoor recreation of carrying gear on one's back, while hiking for more than a day. It is often but not always an extended journey,  and may or may not involve camping outdoors. In North America tenting is common, where simple shelters and mountain huts, widely found in Europe, are rare. In New Zealand, tramping is the term applied though overnight huts are frequently used.  Hill walking is an equivalent in Britain (but this can also refer to a day walk), though backpackers make use of a variety of accommodation, in addition to camping. Backpackers use simple huts in South Africa.  Trekking and bushwalking are other word used to describe such multi-day trips.
Backpacking is an outdoor recreation where gear is carried in a backpack. This can include food, water, bedding, shelter, clothing, stove, and cooking kit. Given that backpackers must carry their gear, the total weight of their bag and its contents is a primary concern of backpackers. Backpacking trips range from one night to weeks or months, sometimes aided by planned resupply points or drops.
Backpacking camps are usually more spartan than campsites where gear is transported by car or boat. In areas with heavy backpacker traffic, a hike-in campsite might have a fire ring (where permissible), an outhouse, a wooden bulletin board with a map and information about the trail and area. Many hike-in camps are no more than level patches of ground free of underbrush. In remote wilderness areas hikers must choose their own site. Established camps are rare and the ethos is to "leave no trace" when gone.
In some regions, varying forms of accommodation exist, from simple log lean-to's to staffed facilities offering escalating degrees of service. Beds, meals, and even drinks may be had at Alpine huts scattered among well-traveled European mountains. Backpackers there can walk from hut-to-hut without leaving the mountains, while in places like the Lake District or Yorkshire Dales in England hill-walkers descend to stay in Youth hostels, farmhouses or guest houses.
In the more remote parts of Great Britain, especially Scotland, bothies exist to provide simple (free) accommodation for backpackers. On the French system of long distance trails, Grande Randonnées, backpackers can stay in gîtes d'étapes, which are simple hostels provided for walkers and cyclists. There are some simple shelters and occasional mountain hut also provided in North America, including on the Appalachian trail. Another example is the High Sierra Camps in the Yosemite National Park. Long-distance backpacking trails with huts also exist in South Africa, including the 100 km plus Amatola Trail, in the Eastern Cape Province.  Backpacking (trekking) is also popular in the Himalayas, where porters and pack animals are often used. 
Backpacking gear begins with (1) a suitable backpack, proper both in size and fit. Backpacks in general fall into one of four categories: frameless, external frame, internal frame, and bodypack. (2) Clothing and footwear appropriate for expected conditions. (3) Sufficient food. (4) Some form of sleep system such as a sleeping bag and, perhaps, a foam pad. (5) Survival gear.
A shelter appropriate to expected conditions is typically next. Practical items not already mentioned - cook kit, stove, container for water, a means of purifying it - are characteristically but not always taken in some form. Depending on the trip ready-to-eat foods may suffice and suitable water be found along the way. More minimalist backpackers find ways to do with less.
Weight is always critical. A rule of thumb suggests a fully loaded backpack should weigh no more than 25% of a person's weight. Every single item is scrutinized, many removed the first time a pack is hefted. Lightweight gear is widely available, which may or may not sacrifice utility and durability but will almost always cost more. A wide variety of items utilizing carbon fiber, lightweight alloys, specialty plastics, and impregnated fabrics are available.
Proper hydration is critical to successful backpacking. Depending on conditions - which include weather, terrain, load, and the hiker's age and fitness - a backpacker needs anywhere from 1/2 to 2 gallons (2 to 8 liters), or more, per day. At 1 kilogram (2.2 lb) per 1 litre (1.1 US qt)  water is exceptionally heavy. It is impossible to carry more than a few days' supply. Thus provisions for adequate water on a backpacking trip must be made in advance, which generally means filtering or purifying natural water supplies.
- Boiling over fire, stove, or other heat source
- Treatment with chemicals such as chlorine or iodine
- Filtering (often used in conjunction with chemical treatments)
- Treatment with ultraviolet light
Water may be stored in appropriate bottles or collapsible plastic bladders. Hydration packs are increasingly popular.
Backpacking is energy intensive. It is essential enough food is taken to maintain both energy and health. As with gear, weight is critical. Consequently, items with high food energy, long shelf life, and low mass and volume deliver the most utility. Satisfaction is another consideration, of greater or lesser importance to all hikers. Only they can decide whether it's worth the effort (and trade-off against other gear) to carry fresh, heavy, or luxury food items. The shorter the trip and easier the conditions the more feasible such treats become.
In all cases, both kit and fuel necessary to prepare and serve foodstuffs selected is part of the equation. Small liquid and gas fueled campstoves and ultralight cooking pots are the norm. Increasingly campfires are prohibited.
While most backpackers consume at least some specially prepared foods, many mainly rely on ordinary low moisture household items, such as cold cereal, oatmeal, powdered milk, cheese, crackers, sausage, salami, dried fruit, peanut butter, pasta, rice, and commercially packaged dinner entrees. Popular snacks include trail mix, easily prepared at home; nuts, energy bars, chocolate, and other forms of candy for quick energy and satisfaction. Jerky and pemmican are high-energy and lightweight. Coffee, tea, and cocoa are common beverages.
Domestic items are typically repackaged in zippered plastic bags. Canned or jarred food, except for meats or small delicacies, is avoided: their containers and moist contents are usually heavy, and the metal or glass must be packed out. Food dehydrators are popular for drying fruit, jerky, and pre-cooked meals.
Many hikers use freeze-dried precooked entrees for hot meals, quickly reconstituted by adding boiling water. An alternative is Ultra High Temperature (UHT) processed food, which has its moisture retained and merely needs heating with a special, water-activated chemical reaction.
These have roots in the U.S. military's MRE, and eliminate the need for a stove, fuel, and water. Against this, they are heavy, the water is already in the food, and they require their own fuel. Still, they have some attractions. They:
- Do not need to be rehydrated or heated, useful where flames are prohibited and water is scarce.
- Are very durably packaged
- Contain a full meal complete with snack and dessert in every package
- Offer a great deal of variety in each meal, including condiments
- Individually package their components, allowing some to be stored accessibly and eaten on the move
MREs can be difficult to find in retail stores, though a good selection is often available in a (U.S.) military surplus store.
Specialized cookbooks are available on trailside food and the challenges inherent in making it. Some focus on planning meals and preparing ingredients for short trips. Others on the challenges of organizing and preparing meals revolving around the bulk rationing prevalent in extended trail hikes, particularly those with pre-planned food drops.
- Survival skills can provide peace of mind and may make the difference between life and death when the weather, terrain, or environment turns unexpectedly for the worse.
- Navigation and orienteering are useful to find the trailhead, then find and follow a route to a desired sequence of destinations, and then an exit. In case of disorientation, orienteering skills are important to determine the current location and formulate a route to somewhere more desirable. At their most basic, navigation skills allow one to choose the correct sequence of trails to follow. In situations where a trail or clear line-of-sight to the desired destination is not present, navigation and orienteering allow the backpacker to understand the terrain and wilderness around them and, using their tools and practices, select the appropriate direction to hike. Weather (rain, fog, snow), terrain (hilly, rock faces, dense forest), and hiker experience can all impact and increase the challenges to navigation in the wilderness.
- First aid: effectively dealing with minor injuries ( splinters, punctures, sprains) is considered by many a fundamental backcountry skill. More subtle, but maybe even more important, is recognizing and promptly treating hypothermia, heat stroke, dehydration and hypoxia, as these are rarely encountered in daily life.
- Leave No Trace is the backpacker's version of the golden rule: To have beautiful and pristine places to enjoy, help make them. At a minimum, don't make them worse.
- Distress signaling is a skill of last resort.
Winter backpacking requires a higher level of skill and generally more specialized gear than in other seasons. Skis or snowshoes may be required to traverse deep snow, or crampons and an ice axe where needed. Winter sleeping bags and tents are essential, as are waterproof, water-repellent, and moisture dissipating materials. Cotton clothing retains moisture and chills the body, both particularly dangerous in cold weather. Winter backpackers stick to wool or synthetic fabric like nylon or polypropylene, which hold less moisture and often have specialized wicking properties to dissipate sweat generated during aerobic activities. Layering is essential, as wet clothes quickly sap body heat and can lead to frostbite or hypothermia.
A winter bivouac can also be made in a snow cave. It has thermal properties similar to an igloo and is effective both at providing protection from wind and low temperatures. A properly made snow cave can be 0 °C (32 °F) or warmer inside, even when outside temperatures are −40 °C (−40 °F).   It is constructed by excavating snow so that its entrance tunnel is below the main space in order to retain warm air. Construction is simplified by building on a steep slope and digging slightly upwards and horizontally into the snow. The roof is domed to prevent dripping on the occupants. Adequate snow depth, free of rocks and ice, is needed — generally 4 to 5 ft (1.2 to 1.5 m) is sufficient. A quinzhee is similar, but constructed by tunneling into mounded snow rather than by digging into a natural snow formation.
Fastpacking is a recreational activity that combines lightweight backpacking with running, and, on steep slopes, hiking. It is a multi-day adventure that usually takes places along long distance trails.   A sleeping bag is carried and other essential backpacking items, and often a tent or similar shelter, if places to stay are not available.  
- Canoe and kayak camping
- Bicycle touring or bikepacking
- Trail riding, where gear is carried in saddlebags
- Backpacking (travel), where public transport is used to visit cultural attractions, rather than natural ones, though it may also include wilderness side trips.
- Adventure travel, tourism in a highly unpredictable or hazardous region or environment.
- Thru-hiking, traversing a long-distance trail in a single, continuous journey.
- Ultralight backpacking, which minimizes both weight and amount of gear carried, typically employed in highly aerobic back-country pursuits.
- Wilderness survival
- "Travel or hike carrying one's belongings in a backpack: [e.g.] a week's backpacking in the Pyrenees, [or] he has backpacked around the world" (New Oxford American Dictionary).
- H. W. Orsman, The Dictionary of New Zealand English. Auckland: Oxford University Press, 1999.
- "Trail Development". Archived from the original on 2014-04-01. Retrieved 2013-12-13.
- Zurick, Pacheco; J.Shrestha; Bajracharya, B. (2006). Illustrated Atlas of the Himalaya. India Research Press. ISBN 9788183860376.
- "Comparisons and Conversions". pp. 2nd paragraph. Retrieved 2009-05-08.
- "Quinzee (aka - Snow Cave)". AlphaRubicon.com. Retrieved 2007-01-30.
- Gerke, Randy. "When Storms Rage (or how to build a snow cave)". Enviro-Tech International. Retrieved 2007-01-30.
- Kate Siber, "Fastpacking: What is it, and why do it?" Runner's World, August 6, 2009.
- Clint Cherepa, "Hike Fast, Sleep Hard: Are You Ready to Try Fastpacking?" Outdoors.org, August 27, 2018.
- Ad Crable, "Running wild", Lancaster New Era, June 18, 1993.
- Patrick Kinsella, "Run, don't walk: mastering the art of fastpacking",Lonely Planet, May 2017.
|Wikivoyage has a travel guide for Wilderness backpacking.|
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