Winter Sports: Where The Action Is

Winter Sports: Where the Action isNew challenges abound at North America's top ski resorts. Here's a look.Big Sky, Montana: With its $2.5 million expansion now complete, Big Sky boasts the highest vertical drop in the U.S. (4180 feet), as well as 1200 additional acres of some of the most advanced terrain in the U.S. Take the 15-passenger tram to the summit of Lone Peak to cruise bowls and chutes that have pitches from 28 degrees to 50 degrees. Or ride the Shedhorn double chairlift to the lower S...