Climbers bivouac outside a hermitage in Europe

In mountaineering, a bivouac, bivy, bivy sack, bivi bag or sometimes, in the UK, Emergency Sack, is an extremely lightweight alternative to traditional tent systems. Very popular among climbers and minimalist campers, a bivy sack at its barest is a thin waterproof fabric shell designed to slip over a sleeping bag, providing an additional 5 to 10 °F of insulation and forming an effective barrier against wind and rain. A drawback of a simple bivy sack is the humidity that condenses at the inner side leaving the occupant or the sleeping bag clammy. Better bivy sacks consist of Gore-Tex (or a similar breathable fabric) to allow the humidity to pass. Image File history File links Metadata No higher resolution available. ... Image File history File links Metadata No higher resolution available. ... This article does not cite any references or sources. ... This article does not cite any references or sources. ... Rock climbers on Valkyrie at The Roaches in Staffordshire, England. ... A sleeping bag is a protective bag for a person to sleep in, essentially a blanket that can be closed with a zipper or similar means, and functions as a bed in situations where it is impractical to carry around a full bed. ... For other uses, see Fahrenheit (disambiguation). ... Gore-Tex membrane, electron microphotograph Gore-Tex (abbreviated GTX) is a registered trademark of W.L. Gore & Associates best known for its use in relation to waterproof/breathable fabrics. ... Waterproof fabrics are usually natural or synthetic fabrics that are laminated to or coated in some sort of permanently waterproofing material, such as rubber, polyvinyl chloride (PVC), polyurethane (PU), silicone elastomer, and wax. ...

Very similar is the swag, very popular in Australia. In popular culture, the term swag usually refers to promotional items or gifts that are given away by companies or organizations. ...

Rock climbing bivouac in Yosemite National Park

Nowadays there also exists the bivouac shelter or "bivy shelter", a compromise between bivy sack and single-person tent. Using hoops or poles, a bivy shelter is usually supported along its length just enough to keep the fabric off of the occupant, and especially to provide some additional breathing room around the head. Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (1280 × 960 pixel, file size: 222 KB, MIME type: image/jpeg) Tenaya Creek Bivouac Description: Bivouac of rock climbers on rock face southeast of Tenaya Bridge, Tenaya Creek Canyon (inset, upper left, shows more detail) Viewpoint... Image File history File links Metadata Size of this preview: 800 × 600 pixelsFull resolution (1280 × 960 pixel, file size: 222 KB, MIME type: image/jpeg) Tenaya Creek Bivouac Description: Bivouac of rock climbers on rock face southeast of Tenaya Bridge, Tenaya Creek Canyon (inset, upper left, shows more detail) Viewpoint... Climbers on Valkyrie at the Roaches. ... Yosemite National Park (pronounced Yo-SEM-it-ee, IPA: ) is a national park located largely in Mariposa and Tuolumne Counties, California, United States. ... A bivouac shelter (also bivy shelter or hootchie) is a simple tent, made from one or two sheets of waterproof fabric and some strong cord. ... This article does not cite any references or sources. ...

In contrast to a bivy shelter, a traditional bivy sack typically cinches all the way down to the user's face, leaving only a small hole to breathe or look through. Many campers gladly accept the increased weight of a bivy shelter for the huge increase in comfort it affords. However, the traditional bivy sack certainly still holds its place among climbers and backpackers, and is frequently carried on long or dangerous hikes and climbs as a compact emergency shelter. Backpacking in the Grand Teton National Park, United States Backpacking (also tramping or trekking or bushwalking in some countries) combines hiking and camping in a single trip. ...

In the UK, Bivy shelters have become very popular amongst Carp fisherman, who, in pursuit of their quarry, fish throughout the night. This upsurge in popularity has increased competition amongst manufacturers and designs have become more advanced. In the UK, they are commonly called 'bivvies'.