Once, chairlifts remained still and ski slopes were unoccupied in the summer. Then, Park City Mountain Resort introduced the Alpine Slide back in the 1970s, and the movement was on.

Today, several Utah ski resorts restart lifts and open slopes to hiking, biking and, in some cases, horseback riding, as soon as weather permits.

The mountain slopes and the higher, cooler temperatures make for ideal day-use outings.

The list of activities available is both unique and, in most cases, very family-friendly.

The alpine slides at Park City and Snowbird allow drivers, often with smaller family members onboard, to negotiate the winding track at their own pace.

The new Alpine Coaster at Park City, one of only three in the United States, not only allows riders complete control but a roller-coaster-type experience.

Hiking and biking, of course, remain the most popular of the summer opportunities. Lift-served biking and hiking take a lot of the work out trying to negotiate the slopes. Once at the top of the lift, everything is downhill from there.

Consensus among several of the resorts contacted is that summer business is good. High fuel prices and the opportunity to spend time in cooler temperatures are attracting people to the resorts.

Even at those resorts that are not open for summer activities, like Alta and Brighton, there is the opportunity to do some hiking or biking.

Following is a list of those resorts offering summer activities:

Brian Head

The resort is well-known for its mountain biking opportunities, not only at the resort itself but also trails, both back-country roads and single track, winding through the Dixie National Forest.

Lift-served trails within resort boundaries range from the six-mile Lightning Point route for intermediates to the Malicious Woods Freestyle Park, with a series of man-made features, like drops, jumps, teeter-totter and S-boxes, for experts only.

What attracts many is the fact that the drop-off point comes in at an elevation of nearly 11,000 feet, and from there it's all downhill. The resort offers shuttle service from locations at lower elevations. Other summer activities include disc golf, hiking and scenic chairlift rides.

Facts: Biking hours 9:30 a.m. to 4:30 p.m., all-day adult rental $30, maps and guides available. The disc golf 18-hole, par-3 course is the longest and highest in Utah. Course free to hikers or with lift pass. Disc rentals available. Lift runs Friday through Sunday. Pass is $24 all day, $10 single ride. Phone: 435-677-2035. Web: www.brianhead.com.