Steep! (and an awesome view)
At approx. 5 miles each way, Mt. Kimball is the most accessible major peak in the Catalinas. At 4200 ft. elevation gain, those 5 miles are tough ones. The peak of Mt. Kimball itself is not much to write home about - it's more or less a bunch of trees. There are no towering rock formations to climb up like Window Peak or Cathedral Peak (also in the Catalinas). But there is a small ledge at the very top which offers a stunning 180 degree view of the northwest side of the Catalinas - which is the prettiest and most dramatic view in the range, in my opinion. When you emerge from the trees at the end of the trail, the view will take your breath away. I've been up there several times, and I still gasp at the view every time. Well worth the trip!
From the parking lot, head up the street a short ways towards the sign for the Coronado National Forest and jump on the trail. After just a few yards, the trail splits off between the Pontatoc Canyon Trail and the Finger Rock Trail. Head out on the Finger Rock Trail.
The first mile or so of the trail is relatively flat, winding northeast through mesquite and suguaro country towards the valley where you begin your ascent. About the second mile, you head steeply up through the valley, in view of Finger Rock much of the way. (Note: there is no trail leading to Finger Rock itself). The views down into the canyon below are impressive. About three miles into the trip, you will approach a saddle known as Linda Vista. There is an un-marked side-trail that splits off to the right for a short distance to the saddle. Linda Vista is a south-facing saddle with a nice view of Tucson below. It makes for a nice place to take a break, or a nice destination for a shorter trip.
Continuing past Linda Vista, you leave the riparian valley for oak and pine country, above and beyond Finger Rock. About mile four or so, you enter a forest of manzanita, and the trail is at its steepest. You will soon reach a Forest Service sign marking the intersection of the Finger Rock Trail and Pima Canyon Trail, noting that Kimball Peak is only 1/2 mile away. Head left* on the Pima Canyon Trail towards the peak. The last 1/2 mile takes you steeply up through a more alpine region to the top of Mt. Kimball. (BTW, at the trail junction, you might want to head just a little ways down the Finger Rock trail to the right - there you can catch a great view of the mountains to the north).
* commonly missed turn, just be aware
The trail will seem to top-out at a point where you can see virtually nothing but the trees around you. There is a side trail heading right (or east) just near the top which takes you maybe 50 yards or so to a rocky ledge which offers the stunning views to the east, west and north. Don't head back without making this tiny side trip to the 'real summit'!
Check out the Official Route and Triplogs.
This is a more difficult hike. It would be unwise to attempt this without prior experience hiking.