Happy Valley campground's name can be decieving.. its actually at 6,000' of elevation, 4.6 miles up the Miller Creek trail in the Rincon mountains east of Tucson. It lies within the Saguaro National Park so a permit is required ($8 fee). Up to 6 people per permit. There is 3 spots at the camp. Each spot has a fire ring, bear box, and some good size stumps to sit on around the fire. There is a vaulted toilet at the site as well. Water can be scarce in the Rincons so plan accordingly!
Another 3.4 miles up the trail and you'll be at the summit of Rincon Peak (8,200'ish).