One of the Summit County resorts, Keystone shares its lift pass and great snow record with Arapahoe Basin, Vail and Breckenridge. It is the definition of American family skiing, with fantastic groomed intermediate and nursery pistes, a great ski school and good childcare facilities. It's a quiet resort with excellent self-catering accommodation and the usual efficiency and friendliness that Americans pride themselves on. There is also night skiing, which covers half of the pistes until 9pm. Keystone also offers great variety for boarders. Advanced skiers may well want to travel to the other resorts for more challenges (A-Basin), while younger people will find nightlife and après-ski somewhat limited. great boarding provision. The town itself is also rather soulless and sprawling, with a lot of the accommodation requiring a free shuttle bus to the excellent lifts. Keystone possesses some of the best on- and off-mountain dining in North America. It is one of the first to open and last to close out of all the Colorado resorts. The resort owners are also building the 'River Run' complex to give it more of a heart.
Keystone has lovely if unchallenging tree-line skiing and is essentially a great family venue for giving American skiing a try. Add to that the shared lift pass and regular buses between the resorts and all skiers will have enough to push them. The major downside is that the resort lacks atmosphere and après-ski, while the high altitude can bring on sickness and nausea. But you can ski until 9pm, so you may be too tired for late nights.