Bonanza Mine Trail

Overview

If you like your alpine views with a side of history, this one delivers. The Bonanza Mine Trail is a strenuous out-and-back climb to a crumbling early-1900s mine perched above the Kennicott and Root Glaciers. It’s roughly 8.25 miles total when you start near the Kennecott Mill, with about 3,900 feet of elevation gain. Starting from the signed junction on the Root Glacier Trail adds about a mile to your day. Figure 4–6 hours for fit hikers, longer if you linger among the ruins or push up the ridge above the mine.

The Experience

The first couple miles are a steady grind on an old dirt road through forest—light on views and heavy on mosquitoes in season. Around the two-mile mark, you’ll catch your first look at Mount Blackburn. By about 2.5 miles the trees thin, the grade steepens, and the glacier panorama opens up. At roughly 3.1 miles an old mining building marks the end of the wagon road; from here the path narrows and points straight at the mine high above.

The upper section is the real workout: very steep, rocky, and loose in places, with waterfalls and big mountain views to distract you between breathers. The mine site itself is dramatic—and hazardous. Structures are deteriorating and the slope is steep; enjoy the history from outside and leave all artifacts where they are. For an even bigger payoff, a short, very steep, unmaintained scramble up the scree behind the mine leads to a ridge with sweeping views.

Why Hike It

Few trails pack this much into a single day: expansive glacier vistas, a tangible slice of mining history, and true mountain effort. It’s demanding, but many hikers call it a favorite for the views and sense of place. Crowds are often light, even in peak summer.

Best Time to Hike

Aim for clear summer days—late June through August—to avoid lingering snow patches up high and to actually see the big mountain views you’re working for. Start early for cooler temps and steadier footing on the descent. Low clouds can erase the payoff, so pick a bluebird day if you can. Mosquitoes can be fierce in the lower forest during the heart of summer.

Logistics and Tips

Park at the end of the McCarthy Road, cross the footbridge, then shuttle or bike the 5-mile road to Kennecott. The shortest start is near the Kennecott Mill; you can also walk about 0.5 mile on the Root Glacier Trail and turn at the signed Bonanza junction (adds ~1 mile round trip). Bring plenty of water and a filter (small creeks appear higher up), trekking poles for the steep, loose descent, insect repellent, sun protection, and bear spray. Check in with the local Park Service office for current conditions and let someone know your plans.

Safety Notes

Expect thigh-burning grades and loose rock near the top—watch your footing, especially on the way down. Do not enter any buildings; the structures are unstable. The Park Service has removed abandoned explosives in the area in the past but warns a few may remain—do not touch suspicious objects and report anything you find. This is bear country: make noise, carry bear spray, and know how to use it. If you’re tempted to continue toward Bonanza Peak beyond the mine, understand it’s an extremely steep, loose, and hazardous undertaking best left to highly experienced parties. As an alternative big day with similar flavor, the neighboring Jumbo Mine route shares a common start and also climbs to historic ruins with big views.