Mountain resorts are becoming more like fun parks built on snowy foundations.

Such retreats now offer activities such as tubing, snowmobiling, skating, cross-country skiing and snowshoeing, in addition to special terrain for skiers and snowboarders.

Terrain parks, featuring a wealth of obstacles that are difficult to negotiate for skiers, have typically been the province of boarders. Now, they are becoming popular with skiers on twin-tip skis, which are designed so riders can take off or land backward.

Massanutten has a terrain park for boarders who want to do more than just carve paths down the slopes. “Snow boarding accounted for 35 percent of our visitors last year,” Showalter says. “Without that, we would be in a deep slump.”

Skiing alone “became stale,” says Michael Valach, director of outdoor activities at the Homestead in Hot Springs. “There wasn’t a lot of excitement.”

Away from the slopes, cross-country skiing is becoming popular, Valach says, in part because of its cardiovascular benefits. It’s also gaining ground among those who enjoy the scenery of back-country ski trails.

The fastest-growing snow sport of all may be just about the slowest: snowshoeing. “It’s really taken off,” Valach says, “especially among women.”

Snow tubing — yes, you ride down the slopes in a giant, inflated tube — also is getting a lot of people to the resorts for the first time. “It’s fun and there’s no learning curve,” Valach says.

Tubing parks offer fun alternatives to skiing and boarding, and remind people what it felt like to be kids on a snow day, grabbing old inner tubes or trash can lids to glide down hills.

Virginia’s Wintergreen Resort, cited by Skiing Magazine as the South’s “single best ski resort,” features a huge tubing park called the Plunge. Wintergreen also has a terrain park for boarders.

Bryce Resort in the mountains of the Shenandoah is expanding its family focus this year, adding a new snow tubing park with three lanes, each about 1,000 feet long.

Many resorts also are finding ways to drum up business year-round.

Massanutten is adding a $20 million water park, which will include indoor and outdoor activities. Wintergreen’s bungee trampoline and climbing tower also will be open this winter on weekends. Many resorts have tennis and golf.

Snow is still king, however.

Here’s what’s new at other East Coast resorts:

In West Virginia, Snowshoe is unveiling $6 million in improvements for its 30th anniversary season.

Snowshoe also is easier to get to, thanks to a faster route that leads to the resort’s new mountaintop welcome center. The change comes soon after crossing into West Virginia on Route 39. Skiers should take Route 92 north to Green Bank and then Route 66 west, following the signs to Snowshoe.

Visitors want to be at the top at Snowshoe. Lodging, food, parking, the comedy club and other clubs, entertainment and shopping are spread along a ridge top, near lifts and slopes.

In Pennsylvania, Camelback is unveiling an upgrade of its snow-making system, says Dave Kulis, an assistant vice president.

“Last season was fantastic,” he says. “Early-season snowfall, combined with excellent snow-making conditions all season, allowed us to post our second-best season in our 40-year history.”

Sugar Mountain, the largest ski area in North Carolina, has a new lift just for its terrain park. Sugar’s tubing park offers 700-foot-long tubing runs serviced by two lifts, and lights for night tubing.

In Maryland, Wisp has added a new terrain park, revamped another and moved its super pipe. “Last season was a terrific year,” says Sarah Duck, a Wisp spokeswoman. “Nature provided us with 215 inches of natural snow.” HS