73.4 miles: 1 hours, 24 minutes
Ease along this serene loop past wide stretches of open land framed by craggy mountains and punctuated by the occasional canyon. Look out for roaming cows and antelope as well as narrow roads on parts of SR 166. Spot Mount Livermore, one of Texas’ highest mountains, midway through your drive. Take a break along the way at a picnic area.