Indoor climbing

Indoor climbing is an increasingly popular form of rock climbing performed on artificial structures that attempt to mimic the experience of outdoor rock. The first indoor climbing gym in the U.S. and Canada was established in Seattle in 1987 under the name of Vertical Club, Inc. It is now known as Vertical World, Inc., which has three gyms in the Puget Sound Area - Seattle, Redmond and Everett.

The proliferation of indoor climbing gyms has increased the accessibility, and thus the popularity, of the sport of climbing. Since environmental conditions (ranging from the structural integrity of the climbing surfaces, to equipment wear, to proper use of equipment) can be more controlled in such a setting, indoor climbing is perhaps a safer and more friendly introduction to the sport. Many rock gyms are settings for birthday parties and youth teams.

The first indoor walls tended to be made primarily of brick leaving little scope for interesting routes, as the steepness of the wall and variety of the hand holds were somewhat limited. More recently, indoor climbing terrain is constructed of plywood over a metal frame, spray-coated with texture to simulate a rock face.

Indoor climbing has also seen an increase in popularity in areas with rainy climates where climbing outdoors is sometimes difficult. Besides offering an alternative during inclement weather, many working adults find that they can get to the gym after work and still climb even though it is too dark outside. In order to improve in any sport, consistent practice is crucial. With the advent of indoor climbing, weather, seasonal difficulties, and busy schedules are less of an obstacle to consistent improvement, and enjoyment of the sport.

Most climbing competitions are held in climbing gyms, making them a part of indoor climbing.

There are a few differences in techniques, style and equipment between sport climbing outdoors and indoors. Climbing artificial climbing walls, especially indoors is much safer because of controlled environmental conditions. During indoor climbing, holds are easily visible in contrast with natural walls where finding a good hold or foothold may be a challenge. Climbers on artificial walls are somewhat restricted to the holds prepared by the route setter whereas on natural walls they can use every slope or crack in the surface of the wall. Some typical rock formations can be difficult to emulate on climbing walls.

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Wikipedia