The backcountry trip near Lake Tahoe where eight skiers were killed after an avalanche was led by a tour outfit that promises global mountain adventures including skiing and rock climbing in the wilderness. The group of 15 was on a three-day trek organized by Blackbird Mountain Guides in which participants carried their own food and overnighted in high-elevation forest huts. They set out on Sunday, the same day that authorities issued an avalanche watch for the area. The tour was rated for intermediate-to-expert skiers. On Tuesday, the group was trapped by an avalanche.