RETRACTABLEROOF
Retractable roof
A retractable roof is a kinetic architectural element used in many sports venues, in which a roof made of a suitable material can readily be mechanically deployed from some retracted or open position into a closed or extended position that completely covers the field of play and spectator areas. They are generally used in locales where inclement weather, extreme heat, or extreme cold are prevalent during the respective sports seasons, in order to allow for playing of traditionally outdoor sports in more favorable conditions, as well as the comfort of spectators watching games played in such weather. Unlike their predecessors, the domes built primarily during the ...The above text is a snippet from Wikipedia: Retractable roof
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