Complex sentence: The ski area is distributed on three mountainsides, accounting for a total of twenty-four trails (CSIA) and the Canadian Association of Snowboard Instructors (CASI), was inaugurated to initiate individuals, young and old, to snow sports.
Split into simpler sentences: The ski area is distributed on three mountainsides, accounting for a total of twenty-four trails. A snow school, which is recognized by the Canadian Ski Instructors' Alliance (CSIA) and the Canadian Association of Snowboard Instructors (CASI), was inaugurated to initiate individuals, young and old, to snow sports.