Weyrs

A Weyr /ˈwɪər/ is a collection of dragons, their riders and support staff in Anne McCaffrey's fictional world of Pern.

The function of a Weyr is to fight Thread, a spore that originates in the Oort cloud of the Rukbat solar system, carried by a planetoid referred to as the Red Star with a loose elliptical orbit. The time during which Thread falls is called a Pass. These Passes last about 50 years, usually with a break of 200 years between, although extended periods have been known to occur due to orbital mechanics.

Weyrs are also the physical spaces in which dragons, their riders and support staff reside. Weyrs are usually built into the cliff faces of ancient volcanic calderas. Many of the living spaces are in natural cave systems within the cliff walls, but in early Passes when the colonists still had technology, plasma cutters were used to create extended systems and additional caves to meet the needs of the growing numbers of dragons. There are six ancient Weyrs as of beginning of the 9th Pass.

Two additional Weyrs were built during the 9th Pass in the Southern Continent, on ground level with sand wallows instead of caves for dragons and built-structures for the use of human residents of the Weyr. A third new Weyr is planned as of the last book.

Each Weyr has a Weyrbowl (the bottom of the caldera) which includes a holding area for fodder for the dragons, i.e. fattened herdbeasts (wherries, cattle, sheep, goats, etc.), a lake or cove (bathing area for the dragons), Starstones to predict a coming Pass as well as many large grassy areas and ledges for dragons to sun themselves.

An individual dragon's 'weyr' (distinct from the complex, denoted by the use of a lowercase) consists of a ledge for landing and sunning, a cavern with a "couch", or raised stone bed (covered with straw or other bedding) for the dragon and sleeping and storage areas for the rider. Some weyrs include a separate alcove for a rider's living area, but smaller weyrs (usually only occupied when the Weyr is very full) have only enough space for a rider to hang a hammock near his dragon and store his gear on hooks. Most weyrs do not have access by foot, the only access being by dragonwing.

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