The vast majority of visitors to Mosquito Flat embark on a day hike of Little Lakes Valley (see guide), but in my opinion, the nearby hike to Mono Pass is the superior option. The 8.75-mile out-and-back trip to Mono Pass takes hikers to the stunning Ruby Lake and the 12,000ft Mono Pass with beautiful views along the entirety of the trail. The Mosquito Flat trailhead starts out at 10,000ft of elevation, and only requires 2000ft of climbing to reach the high point at Mono Pass. In this guide, I’ll provide directions to the trailhead, maps, a gps track, photographs, a detailed hike description, and instructions on booking overnight permits for those that would like to make this a multi-day outing.
Getting There: Directions And GPS Track
- The trailhead for Mosquito Flat and Mono Pass is accessed via HWY 395. The turnoff for this hike is located between the towns of Bishop and Mammoth Lakes on Rock Creek Rd. Head west on Rock Creek Rd for 10.5 miles and you will reach a large parking area.: Mosquito Flat – Mono Pass – Bishop, CA 93514
- The trailhead is located above 10,000ft and passes by a number of seasonal campgrounds. Be sure to check road conditions before your trip by calling the Inyo National Forest office at 760-873-2400.
- Download GPX
- Distance: 8.75 miles
- Elevation Gain: 2116 ft
- Minimum Elevation: 10232 ft
- Maximum Elevation: 12073 ft
- Difficulty: (3.5/5)
- Dog Friendly: Yes, on a leash.
- Permit Required: No for hiking. Yes for overnight backcountry camping.
- Parking: A small lot at the Mosquito Flat trailhead that fills up early. Overflow parking and pullout available further away.
- Water: Many water sources along the trail
- Weather: Warm in the summer months and best from July to early October. After the first snow and ice of the season, this trail is not accessible without specialized gear and mountaineering skills.
- Trail Condition: This trail is mostly single track with a few steep rocky outcrops
- Cell Phone Reception: Patchy to none
To book a permit to camp along this trail, you’ll need to visit Recretion.gov to search for Inyo National Forest wilderness permits. Once there, you can click to ‘Explore Available Permits’ and search for JM08 Mono Pass. Wilderness permits may be reserved up to 6 months in advance for dates between May 1 and Nov. 1 with a limit of 60 people per day. You will need a bear canister, a water filter, and a bag to pack out all trash and waste.
Hike Map And Elevation
Do you have the appropriate gear for this hike? Don’t hike unprepared!
See my current hiking gear list.
0.0 Miles (10232 ft) – Starting from the Mosquito Flat trailhead parking lot, head southwest towards the trailhead. There are pit toilets and bear boxes near the parking area, but in limited supply. This trail gets very crowded in summer, so pack your items up small for the bear bins and be prepared to wait for the pit toilet.
The trail to Mono Pass starts out level and smooth, allowing hikers to warm up and work their way into things. You will hike over a set of stone steps before reaching the junction for Mono Pass vs Little Lakes Valley.
0.5 Miles (10454 ft) – After a half mile of hiking, you’ll see the trail split up ahead. If you go left, you’ll be on the path to Little Lakes Valley (Gem Lakes). You’ll head right here and follow the path for Mono Pass.
After following the junction towards Mono Pass, you’ll climb up a few dusty switchbacks that take you to the top of the valley walls. From here you’ll have a birds eye view of Little Lakes Valley below.
1.5 Miles (10885 ft) – The first set of switchbacks and climbing levels out near a photographic pond that sits just off of the trail. When the water is calm, you can catch Mount Dade and Mount Mills in the reflection.
Leaving the pond behind, you’ll be nearing the junction for Mono Pass vs Ruby Lake. You can choose which site to visit first. Day hikers tend to visit Ruby Lake first and take a break near the water. If you’re backpacking like I did, you can drop your camping gear at Ruby Lake, continue on to Mono Pass, and then make your way back.
1.9 Miles (11044 ft) – As you approach the two mile mark, you can head left toward Ruby Lake or go right for Mono Pass. For this guide, I’ll focus on Mono Pass first. After reaching Mono Pass, you’ll hike back to this junction, and go to Ruby Lake.
After taking the trail towards Mono Pass, you’ll begin to climb a few long switchbacks that provide amazing views of Ruby Lake from above. You’ll also see Mount Dade and Mount Mills peaking out from behind Ruby Lake.
Continue on the switchbacks and you’ll soon lose the views of Ruby Lake, but have the views of Mono Pass up ahead. You’ll be approaching 12,000 ft of elevation here, so the steps might come a little slowly.
3.5 Miles (12072 ft) – At Mono Pass, you’ll have views back towards the peaks surrounding Little Lakes Valley behind you, and the views of Summit Lake up ahead. There is no marker for Mono Pass, but you’ll know by looking at your surroundings that you’ve reached the high point. You can turn back here, but I recommend the short hike down to Summit Lake.
On your way towards Summit Lake, you’ll see Mount Starr to your right. This 12816 ft peak can be reached by following a use trail and then taking on a class 2 scramble to the high point. For this guide, we’ll focus on the short walk to Summit Lake.
Summit Lake is one of those high alpine lakes that makes you feel like you’re on another planet. The views are spectacular in every direction, so give yourself some time to take them all in.
Once you’ve enjoyed enough time at Mono Pass and Summit Lake, you can return the same way you arrived. You’ll see Ruby Lake once again as you descend the switchbacks. When you reach the Mono Pass vs Ruby Lake junction this time, take the leg for Ruby Lake.
We stayed overnight at Ruby Lake for this trip, but it is an equally rewarding stop for day hikers as well. There are numerous developed camp sites, so make sure to pick one and avoid trampling vegetation. There is also a use trail that wraps around the lake, allowing hikers to find a little solitude on crowded days.