Some 400 long-distance runners took to the trails of Sisters Saturday for the Three Sisters Skyline, one of 10 events produced by Alpine Running. Two courses - a half marathon (13 miles) and a 50K (31 miles) - were both challenging and exhilarating, runners said. Photo by Bill BartlettThe half marathon started at the junction of FS Road 1516 and 970 and worked its way south over Peterson Ridge. Three aid stations assisted the 50K runners, with one in service to the 13 milers. Runners ranged from 16 to 73 for the half marathon.