Several years ago Nancy and I hiked to The Window at the top of Ventana Canyon with Diego Moreno and Mercedes Palacios. It's a long, steep hike, but the crest and Window Rock are spectacular when you finally get there, 7000 feet up.
Another great all-day hike is to the top of Mt. Wrightson, in the Santa Ritas, south of Tucson. The summit is over 9400 feet, by far the highest peak for miles around, so there's a spectacular 360-degree view for miles and miles in every direction -- you're just looking down on the world from up there. On a clear day you can see Picacho Peak, 40 miles northwest of Tucson, and probably 50 miles into Mexico, to the south. When Stan Reynolds and I hiked it, it was a 100-degree day in Tucson, but at least 40 degrees colder at the summit, very windy, and the swallows were whirring past our heads, barely missing us as they caught insects there at the top of the world.
Andy Flach maintains an excellent website on Tucson hiking. The site describes many hikes, including directions to the trailhead, length of trail, gain in elevation, degree of difficulty, photos, etc.
Todd Tidyman has a website with a lot of Arizona hiking information. He provides very good descriptions (and photos) of many Arizona hiking trails, including Bear Canyon (Seven Falls), Romero Canyon, and Pima Canyon in the Catalinas. Todd's site also has an excellent catalog of links to sites with information on the Grand Canyon.
A smaller site is Kim Lasota's, which has brief descriptions of several hiking trails in the mountains surrounding Tucson, including the Mt. Wrightson, Finger Rock Canyon, and Bear Canyon (Seven Falls) trails. Kim's site also includes information on equipment, and on particular care one should exercise when hiking in the desert mountains.
Kim's warning that the Finger Rock Canyon trail is very steep is accurate. And a word of advice about Seven Falls: it's beautiful when the water's running, but if you go there on a weekend it will be overrun with people, many of them young people with boom boxes ... probably not the wilderness experience you're looking for. Better to go early on a weekday morning, when you may be the first ones there.

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