Mirror Lake is a 7-acre alpine lake in the Spanish Peaks section of the Lee Metcalf Wilderness, about halfway between Bozeman and Big Sky. The lake sits at the base of Blaze Mountain, surrounded by rocky peaks and year-round snow. For backpackers, this is one of the best overnight trips close to Bozeman. For day hikers, only attempt this one if you're in serious shape, it's 15 miles round trip with over 2,200 feet of gain.
The hike starts at the South Fork Spanish Creek Trailhead, the same trailhead used for Spanish Lakes. You'll follow Spanish Creek through open meadows and dense forest for about 4.5 flat miles. At the junction with Spanish Lakes Trail #411, continue straight on the South Fork Trail. From here the trail turns up Diamond Creek and climbs steeply through switchbacks for the remaining 3 miles to the lake. The lower section is heavy equestrian territory, so expect dusty trails and organic obstacles on the path. Don't be surprised if you see people hiking in with skis or snowboards on their backs in early summer, they're heading for The Blaze, a permanent snowfield on Blaze Mountain.
From Bozeman, head south on US-191 through Gallatin Gateway and into the Gallatin Canyon. Drive about 21 miles and watch for Spanish Creek Road on your left, shortly after crossing Spanish Creek.
Turn left onto Spanish Creek Road and follow it for about 9 miles. The road passes through the Flying D Ranch and is well-maintained dirt the entire way, no high-clearance vehicle needed. You'll dead-end at the South Fork Spanish Creek Trailhead.
The first 4.5 miles along Spanish Creek are flat and easy, the kind of walking you can do while barely paying attention. Don't let that fool you. Once the trail turns up Diamond Creek, it climbs steeply through switchbacks and doesn't let up until you reach the lake.
The distance is the real challenge here. At 15 miles round trip, this is a long day even for experienced hikers. Most people are better off backpacking to the lake and making a night of it.
At 7.5 miles one way, this is a long day hike or an ideal overnight trip. The flat first half moves quickly, but the steep second half slows you down. Averaging about 1.5 mph on the way in, plan on about 5 hours to reach the lake. The return trip is faster with the downhill working in your favor, but you're still looking at an 8-9 hour day if you do it as a day hike.
The trailhead sits at 6,114 feet and Mirror Lake is at about 8,300 feet. The first 4.5 miles along Spanish Creek are relatively flat with minimal elevation change. The bulk of the climbing happens in the final 3 miles as the trail switchbacks up Diamond Creek to the lake basin.
Mirror Lake sits in a rocky basin at the base of Blaze Mountain with year-round snowfields and jagged peaks on all sides. The lake is 7 acres with fish in it if you bring a rod. We arrived completely socked in with fog and couldn't see the lake from 20 feet away. The next morning the clouds lifted and the full basin was right there, peaks, snowfields, the whole thing. If you camp here, that kind of morning reveal is worth the trip on its own.
The trail follows Spanish Creek for the first several miles with consistent water access. The lake at the destination is another obvious source. Bring a filter and you'll have no problems staying hydrated on this one.
At 15 miles round trip, you'll burn through snacks fast. Pack more than you think you need. If you're backpacking, bring a proper dinner and breakfast to enjoy at camp. Stock up in Bozeman or Gallatin Gateway before you go, there's nothing near the trailhead.
The lower trail along Spanish Creek is wide and well-maintained. The upper section gets steeper and rockier as you climb toward the lake, but is still easy to follow. Unlike the Spanish Lakes fork, the Mirror Lake route doesn't have any significant creek crossings.
Plenty of water and shade along the lower trail for your dog. The distance is the main concern. At 15 miles round trip, make sure your dog is up for a long day or plan to backpack so they can rest at camp.
US-191 through the Gallatin Canyon is paved and well-maintained. Spanish Creek Road is dirt but smooth and passable in any vehicle. It's a nice drive through the Flying D Ranch with views of the Spanish Peaks.
Be Advised: Spanish Creek Road is closed to motor vehicles from December 2nd through May 15th.
Beartooth Publishing's Big Sky Area map covers this entire trail and the surrounding Spanish Peaks Wilderness.
There are two parking lots at the trailhead. Aim for the close lot near the South Fork Spanish Creek Trailhead. If you end up in the far lot by the Little Hellroaring Trailhead, you've just tacked on another half-mile to an already long day.
There is a vault toilet at the trailhead near the parking area.
The lower portion of the trail sees a fair amount of equestrian use, so be prepared to yield to horses. Foot traffic to Mirror Lake itself is light. Most people heading up Spanish Creek are going to Spanish Lakes, so once you pass that junction the trail gets quiet.
Bring layers, even if it's warm at the trailhead. The weather at the lake can change fast, and overnight temperatures drop significantly. Trekking poles will help on the steep upper section.
Footwear: Hiking Boots
Expect mosquitoes near the creek and at the lake in June and July. By Labor Day the bugs are minimal. Bring bug spray to be safe.
Good tree cover through dense evergreen forest for the first several miles. As you climb toward the lake, the forest thins and you'll be more exposed. The lake basin has scattered trees but is fairly open.
No cell service from the time you leave Highway 191. Consider bringing a satellite communicator for emergencies.
This is the way to do Mirror Lake. There are established campsites near the lake with plenty of room, and the area allows campfires (check current fire regulations before your trip). The lake is a perfect base camp for a summit push on Blaze Mountain or a traverse into Bear Basin.
Be Advised: This is bear country. Bring a bear canister or hang your food properly.
Spanish Lakes
At the junction about 2.5 miles in, take the right fork onto Spanish Lakes Trail #411 to reach the Spanish Lakes. See our Spanish Lakes trail guide for details.
Summit Lake
Continue past Mirror Lake for another 2 miles to reach Summit Lake, a more remote alpine lake higher in the basin.
Jerome Rock Lakes / Pioneer Falls
At the first major junction about 2.5 miles in, Falls Creek Trail #410 heads to Pioneer Falls and Jerome Rock Lakes.
Plug 15 miles and 2,200 feet of elevation gain into our free hiking time calculator for a personalized estimate.