The Mountains of Arizona •
Union Mine Peak • Peak 2075 • Phoenix Mountains
• Scarlett Canyon Preserve
• Maricopa County

Union Mine Peak

Zoom image highlighting the moon

The Beardsley Boulder Pile

About halfway up

The highest rocks lie outside the enclosure

The summit hidden in palo verde

The thing behind razor wire. It must be important

South view. Behind the freeway is Buffalo Ridge. Behind it is Lookout Mountain. To the left is Shadow Mountain. Way in back, left to right, is Camelback, Mummy, Piestewa, then toward the right, North and Shaw

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Date: October 9, 2017 • Elevation: 2,075 feet • Prominence: 545 feet • Distance: 2 miles • Time: 1 hour • Gain: 535 feet • Conditions: Clear and warm, with cooling breezes


This peak lies north of the Loop-101 Freeway in north Phoenix, the summit less than a mile from the freeway. I don't know what its name is. It is the location of the Beardsley Boulder Pile, a popular bouldering location for years. The old Union Mine was located here, a gold mine dating from the late 19th century. Some sources refer to the Union Mine trails that splay out in all directions from this peak. Thus, Union Mine Peak is as good a name as any. Try as I might, I can't dig up any named reference to this peak.

Back in the olden days (i.e. any time before 1980), it was just an anonymous bump miles from civilization. Beardsley Road ran below the peak to the south, Cave Creek Road to the east. Even when I moved here in 1992, there was no such thing as a Loop-101 Freeway. That didn't get built until about 2000. Since then, suburbia has built up around the area. Now it's surounded by homes and businesses. But evidently, no one has formally named it.

I was here in April, exploring ways to hike this peak. There are trails everywhere ... but no obvious public parking. I suspect most hikers are the locals who live nearby. I tried a few things but didn't feel comfortable with any of the options. Then it got hot. When the heat of summer broke finally, I looked again at hiking this peak. I found where the Beardsley Boulder Pile people go to park, so I figured that would be a good place for me, too.

I left home about 8 a.m., ran an errand or two, got gas, then found myself at the Cave Creek exit off of Loop-101. I went north about 3/4-mile, then left onto Lone Cactus Road a short ways, then south to its end at a turnaround, a parking area big enough for about five cars. No one was here today. There was a Phoenix Parks and Recreation sign and a garbage can here. This was the extent of amenities. It was close to 9 a.m. when I started hiking. The day was sunny and blue, with some haze. It was warm, but pleasant.

I walked west toward the lowpoint in the ridge ahead of me, the location of the Boulder Pile. Here, there are dozens of short routes for boulderers. The trail could be seen snaking up behind the main "Pile". I got onto this trail and speaking of snakes, made sure to keep an eye out for them. It's still warm enough for them to be out and about. Fortunately, I didn't see any.

Near the saddle, I see a young woman inching her way down. She had just hiked the summit wearing cheap flip-flops. I commended her for being so hardy. We talked briefly. I took it that she hiked this spur of the moment. Then a moment later, I see another lady coming down. Given that I was expecting to see no one, I was surprised at the infinite-percent increase in people I saw.

After chatting with the second lady, I marched upward to the top, making it in about 25 minutes. The trail was solid the whole way up. The top hosts some sort of radar apparatus, nothing I've seen before. It stood about 10 feet tall, and important enough to be cordoned off behind fencing and razor wire. Signs about tampering with it were posted. The FBI would be notified. Fortunately, the highest point was a rock outcrop about 8 feet to the northwest of the fence. A palo verde tree grew over the rocks. I tagged them, walked around the fence and sat down for about 5 minutes to rest. The day was warming up, but when a breeze would pick up, it was cooling.

I followed the same route back down, and never saw a soul. I was back to my car in about 20 minutes, the round trip taking just shy of an hour. I got a small workout and hiked another bump I'd never hiked before. From here, I drove home and got busy with other errands I had for the day.

If anyone has definitive evidence of a name for the peak, please let me know.

Update: I have learned that the surrounding area is called the Scarlett Canyon Preserve, and that the peak is sometimes called that name by extension. Thanks to Albert A. of Phoenix for emailing me with this information.

(c) 2017 Scott Surgent. For entertainment purposes only. This report is not meant to replace maps, compass, gps and other common sense hiking/navigation items. Neither I nor the webhost can be held responsible for unfortunate situations that may arise based on these trip reports. Conditions (physical and legal) change over time! Some of these hikes are major mountaineering or backpacking endeavors that require skill, proper gear, proper fitness and general experience. World Hockey Association