The Lake Tahoe region may have the greatest concentration of large cross-country ski areas in the U.S., with more than 800 km. of groomed trails. Most of that is on the north end of the lake, but South Shore has a good network of trails, too. Most also allow snowshoes.

Sierra-at-Tahoe (530-659-7453) has more than 3 miles of groomed snowshoe trails complete with interpretive trail signs. Daily snowshoe rentals and guided tours available. There are no cross-country trails or tours here, but telemark skiers can get tours either in-bounds or into the backcountry, at Sierra's new Telemark and Backcountry Center. Telemark gear is available for rental.

Spooner Lake Cross-Country (775-887-8844, recording; 775-749-5349, live voice) on Hwy. 28, about a half-mile north of Hwy. 50, has more than 80 km. of trails, nearly all of which are machine groomed, with one 19-km. backcountry trail. Lessons and cross-country gear, snowshoe and pulk sled rentals are available; you also can rent a backcountry cabin.

Kirkwood Cross-Country (209-258-7248) has 80 km. of machine-groomed tracks, skating lanes and three interconnected trail systems with three warming huts, including the 1864 Kirkwood Inn, a trappers' log cabin full of nostalgia. Rental gear includes cross-country, telemark, snowshoes and pulk sleds. Lessons are also available. Here's a trail map.

Hope Valley Cross-Country Ski Center (530-694-2266) is near the junction of Hwy. 89 and 88. It has about 100 km. of marked trails, a quarter of which are groomed. Trail fees are by donation. Lessons and rentals are available. The trails at Sorensen's Resort (800-423-9949; 530-694-2203) hook into this system.

Camp Richardson Resort (530-541-1801 or 542-6584) in South Lake Tahoe has a cross-country ski center with lessons, rentals and 35 km. of groomed trails along the Lake Tahoe shoreline. There are additional marked trails venturing into Desolation Wilderness. It's usually voted "Best Place to Cross-Country Ski" by Tahoe locals. You also can get full-moon guided tours, snowshoe rentals, and lodging/cross-country ski packages.

Heavenly's Adventure Peak (775-586-7000) at the top of the gondola includes a cross-country skiing and snowshoeing center. You'll find 5 km. of groomed trails that meander through the forest and provide awesome views from nearly 3,000 feet above Lake Tahoe.