Page Type Page Type: Mountain/Rock
Location Lat/Lon: 32.34630°N / 110.7267°W
Additional Information County: Pima
Activities Activities: Hiking
Seasons Season: Spring, Fall, Winter
Additional Information Elevation: 5506 ft / 1678 m
Sign the Climber's Log


Rocky summit area
Approaching the rocky summit area of UN 5506. | 22 Nov 2012

UN 5506 is a lovely, if scrubby, desert companion to Gibbon Mountain. Easily accessible from where the Arizona Trail reaches the saddle with Gibbon, the curving ridgeline of UN 5506 brings you to a grassy, open summit. From the top, take in views of surrounding Santa Catalina peaks while watching cars cruise the weaving General Hitchcock Highway below. The sparse desert scrub on the slopes makes this peak fairly accessible (by desert bushwhack standards) and the large boulders on top provide a delightful spot to just sit and watch the world go by.

This mountain has seen a lot of history. It rises above a former World War II prison camp where federal prisoners were interned, including Gordon Hirabayashi (for whom the nearby recreation area is named). Ruins of the camp are visible next to the sandy wash below the peak.

Rank: 2516th highest peak in Arizona
Prominence: 366 feet
USGS Quad: Aqua Caliente Hill
Recommended Map: Green Trails Santa Catalina Mountains, AZ – NO 2886S

Rank & Prominence: Lists of John

Getting There

On the summit
Enjoying the summit of UN 5506 on a warm November day. | 22 Nov 2012

Cholla, like this prickly specimen, are common on the slopes of UN 5506. | 22 Nov 2012
This peak can be accessed by trail from many different directions, though most visitors would be content to gain the summit from the General Hitchcock Highway, also known as the Catalina Highway or the Mount Lemmon Highway. The Trailhead by the Molino Basin campground (past milepost 7), a great jumping off spot to reach the summit of Gibbon Mountain, can be reached within an hour of downtown Tucson. Take Tanque Verde (often pronounced “TANKy VURdy” by the locals) diagonally across the northeast edge of town to East Catalina Highway. Follow East Catalina Highway North for about 4.5 miles to the Forest Service boundary. Here the road becomes the General Hitchcock Highway…or the Catalina Highway…or the Mount Lemmon Highway. Take the turnoff for the Molino Basin campground, then head west until the trailhead where the road ends. The trailhead at the Gordon Hirabayashi Recreation Site (former WWII prison camp) also serves a segment of the Arizona Trail.

Note that the highway is paved, but longer vehicles (22 feet or greater) or those towing a trailer may have difficulty negotiating tight curves.
Solider Canyon (Trail #53) or Bear Canyon (Trail #296) would be nice ascent options if wishing for a longer route with greater elevation gain.

Red Tape

Outcrop and moonrise
The moon rises behind an outcrop on the slopes of UN 5506. | 22 Nov 2012
Natural sculpture
They say there are no more desert bighorn in the Santa Catalinas, but - what on earth left THIS sculpture? | 22 Nov 2012
Use of the Mount Lemmon area, including the Catalina Highway, is subject to a $5 vehicle / use fee.

Visit this National Forest webpage for detailed regulations governing use of this area.


Toward Gibbon Mountain
Neighboring Gibbon Mountain from UN 5506. | 22 Nov 2012
Northwest from UN 5506
Views to the northwest from UN 5506. | 22 Nov 2012
The Santa Catalina Ranger District operates several campgrounds along the Santa Catalina Highway to Mount Lemmon. These are (in distance up the highway from the valley):

• Molino Campground (convenient access to UN 5506 form the east)
• General Hitchcock Campground
• Rose Canyon Lake (winter closures apply)

Weather & Seasons

Santa Catalina Highway
Santa Catalina Highway
Ascending UN 5506
Ascending UN 5506

UN 5506 is a year round mountain. Predictably, spring and fall would be delightful times to visit this peak. In the summer, the heat blasting up from Tucson could make it hard to escape the heat. Winter should typically be sunny and pleasant, but can be cold, windy and snowy. Occasional snowstorms slamming the Santa Catalina Mountains might close the “highway with many names,” or at least encourage the Forest Service to put a “4x4 or chains only” rule in effect.

Before planning a trip to UN 5506, I suggest checking the weather both for Tucson, Arizona, as well as for Mount Lemmon or Summerhaven, as the road to the peak will cover both extremes and everything in between.

External Links

Santa Catalina views
Enjoying views from the top of UN 5506. | 22 Nov 2012
Summit Boulder
One of two summit candidate boulders on the top of UN 5506. | 22 Nov 2012
If you have a trip report or other information related to this site, please notify me via Additions and Corrections and I'll be happy to add that link here.



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Santa Catalina SummitsMountains & Rocks