From I5 take highway 22 East towards Detroit for about 50 miles. This exit is right by Salem, OR. 11 miles after Detroit turn left into Whitewater Road (USFR 2243). The sign for the road could be missing so keep an eye for the turn. Take this road to its end about 7.5 miles. Park at the Whitewater trailhead (4100'). The Whitewater trail number is 3429 and follow it for 1.7 miles to the junction with trail 3373. Here turn right and follow this trail as it climbs and finally traverses beneath the slopes of Sentinel Hills with excellent views of the north side of Mt Jefferson. The trail then drops and crosses the Whitewater creek and reaches PCNST after 2.5 miles. Follow PCNST for about 1.5 miles to Jefferson Park a mostly flat area with many lakes and meadows. Near Scout lake turn towards the mountain. It is best to camp here (6000') on a sandy flat area and nearby a creek. Higher up on the mountain finding running water could be difficult.
This route is nicer than the south side routes as the climber gets a panoramic view of all sides of the mountain. The drawback is that the route spirals around the mountain and therefore quite long, so expect a long summit day (12-14 hours). From Jefferson Park climb up the snow fields and morains below the Jefferson Park Glacier, then turn left and climb over the North Ridge to reach the Whitewater Glacier (8000'). Traverse the Whitewater Glacier south beneath the East Face of Mt Jefferson. The glacier is fairly level and straightforward. Stay high on the glacier to avoid the lower crevasses. But also be careful not to get too high because there is constant rock fall from higher up of the east side of the mountain. The easy looking glacier can be deceptive, be aware of the large crevasses which have small openings but if you look inside they go down a long ways. The glacier drops about 100 feet after two thirds of the way and you will see a large crevasse opening up in front of you. This one can be contoured below and around it. Continue traversing southwest until you hit the Southeast Ridge. Jump onto the ridge at about 9000' . The ridge consists of lots of loose rock and scree. It is very easy to start boulder slides so choose the most solid ground, if you can. Follow the ridge until you get to the Red Saddle (10300') beneath the South Horn of the Summit Pinnacle. The crux of the climb is here at the Red Saddle. Cross the steep snow and ice below the West Face of the Summit Pinnacle until you reach the north end of the pinnacle. The runout of the traverse is not good! and there is quite some exposure as you stand on 50+ degree snow. A fall here would have dire consequences as self/team arrest is probably very difficult if not impossible. If you look up you will see lots of loose rock and ice and it can be unnerving to think that all that junk can come down at any moment. Best to move here as quickly as possible. The traverse should be protected with pickets and/or ice screws if the snow allows it. Another complication on the traverse is that there are runnels formed by falling debris or rain and they have to be negotiated. The runnels can be as high as 7' so climbing in an out of these runnels requires special care as their walls are near vertical. Later in the season there would be moats between the snow and the pinnacle which would provide for better protection and footing. Once accross the snow traverse continue a short distance around to the north side of the Summit Pinnacle and follow a class 3 or 4 rock route to the summit.
Return to Jefferson Park by descending the way you came up. If the conditions prevent you to do the traverse back, you can drop from the north end of the Summit Pinnacle west northwest into the Russel Glacier and traverse back to the morains of Jefferson Park Glacier and down to camp. I also heard that there is a possiblity to rappel/climb down the East Face Direct route to the Whitewater Glacier but there is a lot of loose dangerous looking rock to get down.
Ice axe, crampons, helmet, harness and other glacier travel gear, rope(s), prussiks, pulley, biners etc. Bring at least 4 pickets and several ice screws for the traverse. Few passive rock pro could be helpful as well.
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