ASPEN — With 60-plus kilometers of groomed trails, the free Aspen-Snowmass nordic system is tough to pass up. But do so, at least once.

Head instead to Ashcroft Ski Touring, a private enterprise in the upper reaches of the Castle Creek Valley, south of Aspen, for a day on its 35 kilometers of primarily beginner and intermediate trails with the unbeatable backdrop of an historic ghost town and the scenic peaks of the Elk Mountains.

A full-day pass to use the trail system is $15; a half-day pass (after 12:30 p.m.) is $10. There are special rates for senior citizens and children. Ashcroft offers skiing trails, groomed for classic and skate styles, and separate snowshoe trails. Ski and snowshoe equipment packages are available to rent for $20.

The trails at Ashcroft wind through about 600 acres of mostly national forest land, leased for the operation, including winding trails through Aspen groves, open meadows and River Run — a must-do trail along gurgling Castle Creek.

Headquarters for the ski touring operation is the old King Cabin, located at 9,500 feet and open from 9 a.m. to 4 p.m. daily throughout the season. Phone: 925-1971. Purchase a pass to use the system and rent equipment there. Lessons are also available. A 90-minute ski lesson for at least two people is $55 per person, including pass and rentals. Private lessons are $55 for 90 minutes; the pass and rental equipment is not included in that price. A private, full-day lesson is $125, plus rentals and trail pass.

Dogs are not permitted on the trail system, but are allowed on the public road that heads up the valley from the King Cabin. Expect to encounter a horse-drawn sleigh on the road, other skiers, pedestrians, other dogs and snowmobiles.

Combining an outing at Ashcroft with lunch at the Pine Creek Cookhouse is a popular option — so popular, in fact, that reservations for lunch are recommended (925-1044) and required for dinner. You can call up to the restaurant from the King Cabin should you decide a stop at the cookhouse is in order.

The ski or walk up the road from the King Cabin to the cookhouse is a little more than a mile, or take a longer route on the trail system. Horse-drawn sleigh rides between the cabin and the restaurant are also available.

<b>Guided tours:</b> The Aspen Center for Environmental Studies offers guided snowshoe tours and lunch at the Pine Creek Cookhouse. ACES naturalists can identify the multitude of animal tracks you'll see in the snow and expound on the area's history, from the mining town of Ashcroft to one-time visions of a ski area in the valley. For more information, call 925-5756.

<b>Avalanche danger:</b> Beyond the cookhouse, the Ashcroft trail system and the public route into the backcountry pass beneath avalanche slide zones. Some of the groomed trail system may be posted as closed as a result. Danger signs alert users of the public trail that they are skiing at their own risk. Know what you’re doing.

<b>Getting there:</b> Drive 11 miles south on Castle Creek Road from the roundabout on the outskirts of Aspen. When you reach the end of the plowed road, parking for Ashcroft Ski Touring is on the left, just past a parking area for the ghost town, also on the left. The King Cabin is to the right of the road.

A shuttle to Ashcroft leaves from outside the Wheeler Opera House, at the corner of Mill Street and Hyman Avenue, at 10 a.m. daily, according to the Ashcroft brochure. It’s $20 per person with a two-person minimum. The shuttle returns to Aspen at 3 p.m. No reservation is necessary.

<b>One last tip:</b> Bring a camera.