From Sierra Vista proceed south along AZ-92 about 15 miles, following the highway as it bends eastward past the community of Hereford. Turn right (south) onto a paved road leading to the Coronado National Memorial (a sign along the highway will identify the road). Drive south then west for 8 miles to the top of Montezuma Pass. Pavement ends after 5 miles just past the Coronado Memorial Visitors Center. The remaining road is solid hardpack, appropriate for all vehicles in dry conditions (It gets washboarded a bit, beware). Go slow along the narrow curves and steep grades. A large parking area is available at Montezuma Pass.
This is one of many possible ways to get high onto the Huachuca Range Crest. Walk across the road and find the signed trailhead, which shows Miller Peak as being 5.3 miles distant. The route is all trail and very easy to follow.
The trail contours around and behind a small hillock, comes to a saddle then starts a long series of sweeping traverses and switchbacks up a mostly open hillside below Peak 7,964. Three open mine tunnels and adits are found high on this section. Shortly the trail surmounts the ridge a bit southeast of Peak 7,964. Bear left, pass the National Forest Boundary and proceed in a northerly direction, with Miller Peak coming into view for the first time. Stands of trees offer shade, but much of this hike is amid short manzanita scrub with little shade, which can be uncomfortable in hot conditions.
The route proceeds northerly, occasionally switchbacking, and crosses the ridge crest to work its way along the west-facing slopes a bit. It will eventually meet the trail coming up from Lutz Canyon. The last mile or so is up rocky switchbacks and some sections of forested cover. Elevation gain is about 2,900 feet.
This route is apparently popular with the border crossers coming up from Mexico. Montezuma Pass is just about 1.5 air-miles from the border. My wife and I encountered a pair of Mexican men who were obviously crossers themselves, or 'agents/guides', so to speak. We spoke briefly in Spanish. We later met up with two heavily armed Border Patrol agents running the trail, looking for a large group. Much of the route is littered with cans and bottles and clothing. It's actually a pretty route, marred by the trash. The BP agents said the crossers will generally leave casual hikers alone but nevertheless one should be aware while following this route.
Long pants, hat, plenty of water, Spanish phrasebook.
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