Like many of its Beaverhead cousins, Ajax Peak sits on the Continental Divide in the northern end of the Beaverhead Mountains. Topping out at just over 10000' it is easily seen from US 93 in Idaho. From Montana it sits much further away from Hwy 278 on the western horizon and is harder to see unless you know which peak to look for.
You can find Ajax in Tom Lopez' book Idaho A Climbing Guide. Pat Caffrey has a 15 word description on Ajax Peak in his book 'Climbers Guide to Montana'.
The Ajax Lake basin has been the site of a colorful past. The Ajax Mine is located on the south side of the basin below Peak 10042. The mine shaft entrance is still plainly visible once you gain some elevation and has a primitive road leading to it. You will also be greeted by an old cabin as you first approach the lake.
The other striking feature is a past fire that has left many charred and barren trees still standing guard on a good portion of Ajax Peak's lower slopes.
Access is best from the Montana side as the road system can take you to Ajax Lake which sits below the peak. Idaho access is via Carmen Creek Road.
The closest towns are Wisdom in Montana and Salmon in Idaho which both offer gas, groceries, and meals.
Key access highways are US 93, MT 43, MT 278, and I-15.
Take the Twin Lakes campground exit 6.6 miles south of Wisdom, Montana on MT 278. Travel 8.2 miles to a sign pointing south to Big Swamp Creek Road. After 8.4 miles on a good gravel road, turn right onto Big Swamp Creek Road 625. Another 4.8 miles takes you to a sign pointing to Ajax Lake. Another 3.1 miles takes you to a point where the road kicks up sharply with some serious rock in the road. From here you will need 4WD to negotiate the steep kickup and the final stretch of very rough, steep road leading to the lake. Otherwise, you can park below the steep kickup (2 spots) and hike up to the lake.
The Forest Service roads are closed to motorized traffic (except snowmobiles) until May 15. Thanks to Arlee for providing this information.
Take Carmen Creek Road which is located 4 miles north of Salmon on US 93. After 5.1 miles the pavement ends and the road forks. To the left, Carmen Creek Road continues and to the right is Freeman Creek Road.
From the fork you have a couple of options. First, you can take a right up Freeman Creek Road, then a left which eventually ends at some private residences. You can park below and out of sight of those residences, but are left with a decision to cross privately owned hay fields commando style or ask for permission.
The second option is to continue to the left up Carmen Creek Road. If you drive far enough (3-5 miles) this should put you beyond the private property and hay fields and allow you to get into the foothills for your ascent.
Best tip: The drive in on the paved portion of Carmen Creek Road gives you a clear look at Ajax Peak and the opportunity to assess and select your best route.
Starting elevation for both options is in the 5000' range.
1) Ajax Lake (south ridge) route Class 2
From the lake, make your way around the right side of the lake on a faint trail over rocks and downed trees.
Just before you reach the far west end of the lake, make your way up through rocks, boulders, scree, and scrub. If there is a section which might have a mix of some Class 3, this is it. At about 9150' you should run into an obvious trail that leads to the south ridge.
From the ridge, a right turn and roughly 600' of bouldering will put you on top. You may use your hands in a couple of spots, but only for balance or to manuever.
Ajax Lake elevation: 8522'.
2) East ridge Class 4
Climbers Guide to Montana states: "The east ridge has a little C-rated climbing". C-rated = Class 4. You could certainly get on to the east ridge from where you first approach the lake. Thanks to Fred Spicker for providing this information.
This summit sits 1.25 miles south of Ajax along the divide. The actual Ajax mine entrance is located on the lower slopes of this peak. With no obstacles and a common saddle at 9300' you can expect a Class 2 traverse with 4 or 5 interesting cairns along the route to amuse you.
At the risk of raising strong opinion, I would like to name this one Don Moore Peak.
Don's parents homesteaded in Montana's Teton and Choteau counties around 1910. Don was a WWI veteran and returned to Montana to be a life long grain grower. Later Don added the service of being a rural letter carrier to his resume'. Granted Don did not spend his time in the Big Hole Valley, yet he represents all the unknown men and women who helped shape Montana into the state it is today.
Don Moore was my grandfather.
Located in a glacial ampitheater occupied by Ajax and Lena Lakes at an elevation of 9000', the Ajax was first discovered in 1874.
The Ajax produced gold, silver, copper, and lead. At the height of operation in the early 1900's the property had a stamp mill, sawmill, and boarding house for workers.
Although the mine continued to produce ore, the owner Alva J. Noyes, lost money and had to sell his ranch in the Big Hole Valley to pay his creditors. By 1905 the mine was closed.
Although the Ajax saw brief mining activity in 1915 and then again in 1935, the glory days were long past.
A more detailed historical account can be found here.
The closest campgrounds are Twin Lakes and May Creek which is located on MT 43. These are Forest Service campgrounds with fees and stay limits.
Once you drive into the forested foothills, it is possible to pull off the road and set up camp in numerous places. Many of these spots are obvious and have certainly been used for many years. You will be left alone as the Big Hole is remote country.
Setting up camp at Ajax Lake can be done as well.
Road and mountain conditions are available through the Wisdom Ranger District at 406-689-3243.
In Idaho, Salmon Field Office at 208-756-5400.