This trail starts just after finishing the fun downhill of Los Caracoles. Take the first left down a short, steep hill followed by over 1 km of climbing that you won't think you'll finish. At the top there is a nice place to stop and rest and take a picture of Hermosillo.
Once you pass this lookout in another 500 meters there is a Y in the road - stay to the left. To the right is the trail McDonald. The trail is very straight forward with some technical areas, but not too difficult.
After a long climb in a wide rut, there is a short downhill where you take a right at the bottom. (Going straight is a different tail called Adrenalina - there is a sign). Take a sharp right under a Paloverde tree and in between two large black rocks. The next section is some rocky, flowy section followed by sandy downhill. You can get up some nice speed here before getting to more uphill rock garden. Take care as there are a few unseen rocky drops.
The trail comes to a T joining another trail, take a sharp left and follow for a short uphill (staying to the left and passing some trail offshoots). You'll pass a Virgin of Guadalupe shrine at another overlook and veer to the right for the very fun and fast final 1 km downhill.