A lovely rolling 70 mile ride, with 3,350 feet of climbing and some wonderful views.
Drive down I-19 for 37 miles from the intersection of I-10 and I-19 then take Exit 48 to Arivaca. Turn right, then at the T-junction turn right again and park in one of the big parking areas. We parked at the closed Longhorn Grill.
Head west on Arivaca Road and follow the road as it rolls uphill for 20 miles to the high-point. From here it rolls downhill for 3 miles to the pretty little town of Arivaca. (At 21.7 miles there is a coffee shop on the right which is open until 2 pm. We stopped here on the way back.)
Ride through Arivaca and follow the road as it curves right. The road surface for the next 12 miles is noticeably worse than the first 23 miles with occasional potholes in the road. However it’s a pretty ride with amazing views of Baboquivari in front of you most of the way. 12 miles from Arivaca you reach Highway 286.
Turn round here and ride back the way you came. You’ll be surprised at how much climbing you have to do to reach Arivaca again. Climb out of Arivaca and follow the road as it rolls downhill to I-19. The last few miles have wonderful views of rocky Elephant Head. Behind this and to the right you can see the observatory at the top of Mt. Hopkins.