The Forrest Service grooms the Little Mill and Granite Flat campground roads for skate and classic skiing. They also groom the Alpine Loop and Silver Lake roads for snowmobiles but they are good for XC skiing. See the Google map link for a more detailed map with the following areas indicated:

Little Mill parking - Park here to ski up the Little Mill campground road. The sign says Sawmill. Distance is about 1.1 - 1.2 miles (1.8 - 2.0 km) to the end. Classic tracks set after the hill. Groomed twice a week.

Pine Hollow - Park here and ski up the road. Groomed for snowmobiles and usually in good condition. Plenty of opportunities for off-track skiing, like the Timpanogos Perimeter road.

Tibble Fork - Park here for access to Granite Flat, Silver Lake Flat, etc.

Granite Flat - Closed to snowmobiles and groomed for XC ski. Classic tracks are set where possible. Start with Tree Army loop then take the Barracks and Spike loops. Distance is about 1.7 miles (2.7 km), plus 0.8 miles (1.3 km) if you take the Silver Lake road to get to Granite Flat. Groomed once a week.