What is Picketpost Mountain?
Picketpost Mountain is the flat-topped block of volcanic rock that sits alone on the south side of US 60 as the highway drops toward Superior, named for the picket post the Army kept on it in 1870 to watch over the camp that became the town. It tops out at 4,378 feet, about 2,000 feet above the desert at its base, and the way up is a classic: about 2.3 miles one way, the first mile on the Arizona Trail through saguaro and grass, then a signed turn onto the mountain and a steady steepening into chutes, slabs, a slickrock gully that runs after rain, and loose stone, marked by cairns and painted arrows on the bedrock. Most of the upper route is class 2 with a few class 3 moves; see scramble and class ratings if those terms are new. The summit is a broad plateau, and a half mile across it at the far edge stands a mailbox holding the summit logbooks, which people have been signing for decades.
The trailhead is a hub. It is the north end of Arizona Trail Passage 17 (Alamo Canyon, 11.6 miles south) and the start of Passage 18 (Reavis Canyon, 17.8 miles north to Rogers Trough), and a popular 8.6-mile loop uses the AZT and Alamo Canyon with about 1,000 feet of gain for those who want the country without the scramble. Boyce Thompson Arboretum sits at the mountain’s northeast foot, three miles east by road.
What you get is the best short hard hike within 90 minutes of Scottsdale, free, with toilets and a view from the Superstitions to the Pinals. What you do not get is water, shade, a sunrise start, a trail you can follow without looking, or a route a dog or a nervous scrambler can do.
How to hike it right
Pay nothing, mind the gate. No fee is posted and no Tonto Pass is needed. The Forest Service closes the gate from dusk to dawn; a site host is on hand so nobody gets locked in, but you cannot start a sunrise hike from inside the gate and late arrivals are not admitted. Plan to be back at the car with light to spare.
Get there. Loop 101 south to US 60 east, through Apache Junction and Gold Canyon, past Florence Junction and up the long grade toward Superior. Just east of milepost 221, about 4 miles before town, a signed turn goes south on Forest Road 231; in 0.4 miles turn left on Forest Road 310, go 0.6 miles and turn right at the Picketpost Trailhead sign. The road is smooth dirt any car can handle. The lot is large, with vault toilets, a big metal Arizona Trail sign and room for horse trailers. About 75 minutes from Old Town.
Pick the season. November through March. The route faces north and west and holds a little morning shade, but the slabs are in sun by ten and far too hot to handle from May through September. The summer rules apply, and the gate hours make a true dawn start impossible anyway; in April and October go on a cool day and start the moment the gate opens.
Water. None at the trailhead or on the mountain. Three liters per person for the summit.
Find the turn, then trust the arrows. Leave the Arizona Trail at the signed Picketpost Mountain junction about a mile in, not at the first wash that looks like a route. Once on the mountain, follow the painted arrows over your own line; the chutes all look climbable from below and only the marked one goes cleanly, and people get stuck on the wrong slab every winter. Allow four hours round trip even though it is barely five miles, and set a hard turnaround by early afternoon, because every slab you climbed up is slicker on the way down. Gloves save your hands on the rhyolite.
Cross the summit. The plateau is broad and the mailbox is a half mile across it at the far east end. Sign the book, read a few, latch it, and walk to the south edge for the view of the Superior copper country and the Pinals.
Dogs. On leash on the AZT and the Alamo Canyon loop; not on the summit route, where the slabs and chutes require lifting a dog and the rock is hot.
Split a mixed group. Send the scramblers up and have the rest do the 8.6-mile Alamo Canyon loop from the same lot, or spend the morning at the arboretum three miles east and meet for lunch in Superior.
Skip it if two thousand feet in 1.3 miles on loose rock is not what you came for. It is a Flatiron-grade effort with less traffic and fewer people to follow; the Flatiron itself has more hikers to learn from, and Peralta delivers the Superstition view on a real trail. For a night nearby, the Oak Flat Campground east of Superior is free, and sits on the ground the Resolution Copper fight is about.
The sentinel post that outlived its camp
The mesa was a lookout before it was a hike. The Queen Creek country at its foot was Western Apache range, and the Hohokam and Salado farmed the creek before them; a flat-topped mountain visible from the Gila to the Pinals was a landmark on every route through. In 1870 General George Stoneman established a military camp at the mountain’s base to cover the road east, and his soldiers posted a sentinel on the summit to watch for Apache raiders. They called the mountain Picket Post, and the name outlasted the camp, which grew into the town of Superior. In 1872, according to local legend, cavalry from the picket ambushed a raiding party whose survivors retreated over the cliffs east of town that are still called Apache Leap.
Silver, then copper, made the town. On March 22, 1875, Charles Mason’s party struck native silver and staked the Silver King, and the Silver Queen vein was staked a week later. Both played out in the 1890s. In 1910 William Boyce Thompson, a Montana-born mining financier, and George Gunn bought the Silver Queen and organized the Magma Copper Company; a concentrator came in 1914, a railroad in 1915 and a smelter in 1924, and the Magma Mine ran, with interruptions, until it closed for good on June 28, 1996. Superior itself was platted in 1900 as Hastings, laid out as Superior in 1902, and has lived and died by copper since; Resolution Copper’s exploration of the deep ore body under Oak Flat, from the old Magma No. 9 shaft, is the latest chapter, and the most contested.
Thompson also planted the mountain’s garden. On April 1, 1924, he founded the Boyce Thompson Southwestern Arboretum on the grounds of his Picket Post House below the mountain’s northeast face, hiring its first two employees from the University of Arizona; it opened to the public on April 6, 1929, became a state park by agreement on March 30, 1976, and remains the oldest and largest botanical garden in Arizona, 392 acres along Queen Creek. The Picket Post House itself was sold in 1946 and bought back by Arizona State Parks in 2008.
The trailhead belongs to the Arizona Trail. Dale Shewalter, a Flagstaff schoolteacher, proposed a border-to-border trail in 1985; the Arizona Trail Association incorporated in 1994 and routed its line past Picketpost, making the mountain’s foot the junction of Passages 17 and 18 and the natural place for a developed trailhead. Congress designated the Arizona Trail a National Scenic Trail on March 30, 2009, and the 800-mile route was declared complete on December 16, 2011. The toilets, the big metal sign, the horse-trailer parking and the gate that locks at dusk date from the trail’s build-out; the painted arrows on the summit route and the mailbox on top are older, informal and unsigned, maintained by the people who use them. Nobody this guide could find has written down when the first logbook went into the box.
What is coming is the mine. If Resolution Copper’s land exchange and block-cave operation at Oak Flat proceed, the subsidence crater and the tailings will reshape the country east of the mountain, and the view from the south edge of the plateau will change within the lifetime of anyone reading this.
Why it matters
Picketpost explains Superior, and Superior explains a great deal of Arizona: an Army post, a silver strike, a copper company, a financier’s garden, a closed mine and a new one waiting, all within sight of one mesa. The hike up it is the state’s clearest short lesson in how a scramble differs from a trail, and the mailbox on top is one of the few places where decades of ordinary hikers have left a record in their own hands. For a Scottsdale hiker the verdict is firm: between November and March, on a cool morning, with gloves, three liters and a hard turnaround time, this is the best hard half-day within 75 minutes of Old Town, and the arboretum below it is the right way to finish.