Drive up Zimmerman Trail from Billings and turn left at the top the parking lot is on your left.
The loop depicted is the primary loop in the park. There are several optional routes that spur off of this loop. Sandstone and dirt singletrack. The area can be ridden as a short 20 to 30-minute loop, or can be ridden for a few hours with many natural features to play on. Excellent views. Can be as technical as want it to be.
Warning! On nice evenings and weekends, it can become busy with dog walkers as well as people seeking views of the city.