Night skiing

Night skiing is the sport of skiing or snowboarding after sundown, offered at many ski resorts and mountains. There are usually electric lights – including LED lamps – along the piste which allow for better visibility. It typically begins after a resort's skiing-day ends (sunset), and ends between 8:00 and 10:30 p.m.

Night skiing offers a few last runs for busy skiers who don't have time to ski during daylight hours. Trails at night are normally not as busy as during the day, but there are usually fewer runs available. The trails also tend to be icier than during the day, due to melting and refreezing.

Night skiing was invented by Webb Moffet who used to own a ski area near Seattle, which is now called Summit West. He bought huge flood lights and aimed them at the hill, so his employees could have some fun after the customers went home. After a while, it occurred to him that people would pay to ski at night, and so it became part of the business.

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Wikipedia