Hunter trail to the top of Picacho Peak is the shortest route., but also the steepest. It is 2.7 miles round trip with an elevation gain of 2090 ft! The hiking Difficulty calculator rates it as extreme! That may be why after hiking it I experienced cramps! It is tough on senior hikers. There is cables to assist you in some spots. So wear gloves. Hiking sticks on the lower portions will be helpful, but be prepared to stow them on the upper portions. No bouldering or rock climbing on the route and the trail is well defined.
Trail surface for the most part is hard packed earth, although some areas are rock. Take plenty of water! Have a snack at the top! Enjoy the view.