For the first time since its tram opened in 1994, Alyeska Ski Resort will let mountain bikers take their bikes uphill in the tram for a rousing ride down later this month.

The tram ride lasts seven minutes. How long the 31/2-mile descent down 2,200 vertical feet takes will depend on a biker's skill -- and courage. Top downhillers should be able to make it in about 20 minutes.

For now, downhill riding at Alyeska is a one-day affair on Sunday, Sept. 19, costing $30, with the tram taking bikers up the mountain between noon and 5 p.m. The Girdwood resort plans to offer tram rides for bikers on Saturdays and Sundays all next summer.

"It's a historic event for Alyeska," said Di Hiibner, Alyeska's general manager. "We've been getting requests for years and years. It's something that we always wanted to do, and now we think the trails are ready."

Downhill riding is aimed at intermediate or advanced mountain bikers, and Alyeska is limiting the number of riders to 200. They'll be organized into groups of similar ability and paired with a guide. The tram will run rain or shine.

"I've been waiting and hoping this would happen for years," said Kevin Murphy, a 22-year-old bike builder at Paramount Cycles during the summer and a UAA student during the cooler months. "I think the mountain is an untapped resource for mountain biking. You could have everything from beginner to expert rides there."

Murphy is among the handful of local cyclists determined enough to push and pedal his way up the mountain just for the thrill of the downhill ride.

"I'm proud to be part of it," said Jake Young, the supervisor for hiking and biking programs at Alyeska. "Ten years ago, people were talking about biking on the tram -- but Alaska is a little behind in more ways than one.

"Basically, the way I've always seen it is that downhill biking is a summertime version of skiing. ...There's kind of a depression at end of ski season. It's like, 'Oh no, what are we going to do all summer?' "

Ski resorts like Whistler in British Columbia have partially answered that question with mountain biking. The popular Whistler Mountain Bike Park has become a big moneymaker for the resort.

For now, though, Alyeska is starting small.

"We're trying to make the trails user-friendly for all levels," said Young, 33, who has worked at Whistler. "But you need rudimentary skills."

Helmets will be required -- they're available for rent for $5 -- and staffers will be on hand to assist. Riders under 12 won't be allowed and those under 19 need a parent or guardian present to sign a liability release.

"If they don't own a bike and they haven't biked for years, it's probably not for them," Hiibner said. "We want people to have good equipment."

Whether downhill biking can take root here the way it has in British Columbia is unclear. British Columbia has a rich mountain biking history and an ingrained action-sports culture. In Alaska, downhill biking is a tiny segment of the mountain biking community, which itself is just a slice of Southcentral's bikers.

"There can't be more than 40 or 50 people who have the equipment," Young said. "But with lift access, the population will grow. I'm hoping for a potential boom -- or at least an increase.

"Alaskans are proud enough and adventurous enough."

Downhill biking culminates three years of determined trail building at Alyeska that includes the opening of the scenic North Face Trail last August and the completion of the Winner Creek Extension Trail two months ago.

At the same time, work on such trails as the Bear Cub Climb, Blueberry Hill, and Christmas in July have made them more bike-friendly. Last summer, the Blueberry Pancake trail through heavily wooded terrain opened for downhill bikers.

Of course, mountain biking is a seasonal affair at Alyeska. This year, the 526 inches of snow that fell at mid-mountain didn't melt until the end of July.

Next summer, Hiibner said, the resort expects to offer weekend downhill mountain biking once the trails firm up.

Downhill bike race at Arctic Valley

On Sunday, Arctic Valley Ski Area will host a race to gauge interest in downhill racing. Registration is 9:30-11:30 a.m., with practice at 10:30 a.m.

Racing starts at noon at the top of Chair 3, heading downhill to the parking lot by the coffee shop. Racers will leave at one-minute intervals.

Cost is $30. Register online at skiarctic.net or at Don Jose's restaurant, 2052 E. Northern Lights Blvd. For information, call 350-6664.