From the bottom, the hill didn't look so steep. Now, standing at the top, it's a little intimidating. But what the heck. You're here, you've paid your fare, and now it's time to take the plunge.

So you flop down on your sled or tube and push off.

The world whizzes by at 30 mph and you're just inches from the snowy crust. Your hat may fly off and your sunglasses become dislodged as you let out a squeal of joy. You're 6 years old again and the hill is yours. Finally, you reach bottom, slow down and come to a dizzying stop. Out of breath from excitement, you hop on the lift to do it again.

Crested Butte Mountain Resort

A family slides down the tubing hill together at Crested Butte Mountain Resort in Colorado

Clearly not all the fun on Colorado snow happens on skis. For some of the wildest thrills, get down on the ground on a tube or sled.

You don't need lessons, expensive equipment or special skills (such as hand-eye coordination) to do this. And it's a great way to introduce kids to the thrill of the hill in a fun and nonthreatening way. (Note: Most commercial sites require that kids be 36 inches tall to ride alone; otherwise, they can team up with an adult.)

Tubing may be the fastest-growing snow adventure, says Bob Nock, owner of Meadow Mountain, a tubing hill in Minturn, Colo., near Vail.

"It's just a great alternative to skiing, especially for families," he says. "Not everybody skis, but everyone can ride a tube. We can hook up to eight tubes together and give them a little spin for a really fun ride. And you can do it together. Skiing really is an individual sport."

Tubing is so popular that most Colorado ski resorts have added it as an option, and almost all the hills have lifts and groomed runs.

"Lifts have really changed the face of tubing," Mr. Nock says. "You don't have to haul the tube back up the hill before you ride down again."

The average customer gets 10 to 12 tube runs for an hour's fee.

And though adults love it, "the kids are unstoppable," he says.

The sport also is very safe, he adds. After two seasons, Meadow Mountain hasn't had a single injury.

Most tubing sites charge $20 an hour or less, including use of the tube or sled.

So next time you get tired of tromping around in ski boots, grab something that slides and shove off.

Where can you experience this safe but exciting adventure? Check out the Colorado options described here.

Between the towns of Winter Park and Fraser, there's a tubing hill that will knock your wool socks off. Get there via a free shuttle bus from town. The groomed, lighted hill has a tow-lift system so you can save your energy for the ride down. You can hook up with others in tandem or groups for a really high-speed excursion down the slope with a long run-out. It gets busy, so go early in the day or on weekdays.

970-726-5954, 970-726-4118 or 1-800-903-7275; www.winterpark-info.com

You can hear the screams before you even enter the East Village at Copper Mountain. At the base of the SuperBee Lift, catch the Stinger surface lift for a ride to the top of the tubing hill. This place has groomed lanes so many tubers can run at one time. Reservations recommended.

1-866-841-2481; www.coppercolorado.com

You have two options at this resort. The old-fashioned family tubing hill is located at the Keystone Nordic Center. For more extreme tubing, catch the lift and hit the summit of Dercum Mountain at Adventure Point. With a good pitch and long run-out, you're sure to get an adrenaline rush. Reservations recommended.

970-496-4386; www.keystone.snow.com

As the light begins to fade, the ski hill transforms into a tubing hill to help extend your day of snow fun in the mountains. If sledding is your sport, the Nordic Center and Ice Rink complex also offers that. And you'll likely see a few parents using sleds as transportation, hauling their kids around town so little ones don't have to trudge through snowdrifts. Just watch out for traffic.

970-349-2211 or 1-800-544-8448; www.skicb.com

Situated between Vail and Beaver Creek, Meadow Mountain in Minturn gets its share of snow. Tubers can ride the lift up to the top of the groomed runs, which are unique because they include four banked turns. Riders can strap together for a spinning-doughnut effect. You'll hear the laughter a mile away. To warm up, you can buy a bowl of soup, a hot dog, coffee or hot chocolate on site.

970-827-4155

Snow tubing joins snow-biking, snowshoeing, ice skating, a trampoline and snowmobile rides for kids at this all-purpose activity center. Kids 5 and younger must ride with an adult. But that's OK, because this place is geared for families. A lift serves the tubing hill, which has multiple lanes.

970-476-9090; www.vail.com

Both guests and nonguests can take in family-style tubing at the Snow Mountain Ranch near Granby. It has a lift, and it's an easy run for the very young and the not-so-very-young.

303-443-4743; www.ymcarockies.org

Linda DuVal is a freelance writer in Colorado Springs.