This is the Sweetwater trail that starts at the west end of El Camino Del Cerro and leads up to Wasson peak, the highest hill in the Tucson mountains.
UPDATE: I hiked the trail again this last Saturday and made it to the top this time!
The trail is a 9.3 mile round trip, and the summit is 1900 feet above the parking lot, though the total elevation gain with all the ups and downs is 2600 feet. This is the Google Earth video of my hike (GPX file available here):
This is a panorama from above the saddle, giving a good view of the Tucson Mountains to the south. Kitt Peak is in the distance on the right.