GLENWOOD SPRINGS — Skiers looking for new thrills and are heading to ski resorts after dark, filling parking lots and climbing ski runs after the sun goes down. It's all part of a sport called "uphilling," and it's seeing a big surge in popularity. In addition to Aspen Skiing Co.'s four mountain ski areas, Sunlight has helped make the valley a destination, with the support of ski areas, compared with other areas of the country that have limited or even prohibited uphill skiing. The Glenwood Springs Post Independent reports (http://tinyurl.com/hqqzosa ) resorts are setting rules to make safety a priority, including requirements to avoid ski grooming and other equipment that are used on ski routes after the day Read more on Colorado Springs Gazette