There are wonderful, open trails in Tucson Mountain Park, about a ten minute drive east of Tucson. The Marriott Starr Pass Resort is located at the gateway of the trails. There are numerous options here — many of them more modest for trail running.
The Starr Pass Trail Loop is a beautiful 4.7 mile run, that is good for all running levels. Offering hills, relative flats, and varied terrain, the trail is regarded as especially beautiful in the mornings and evenings, featuring views of Tucson and Mt. Lemmon.
If you’re a more advanced runner, and looking for something a bit more challenging, there is an 8 mile loop, that extends off the trail. Note that if you’re visiting Tucson in the summer, you want to carry plenty of water and avoid mid-day runs, because there is little shade on this trail.