To reach Chicago Basin, use the
Approach Page. From your camp in Chicago Basin, hike northeast toward the end of the basin on the great trail -
1. Near 11,200', turn left toward Twin Lakes at a signed junction -
2. This trail is used to reach Windom, Sunlight, and Eolus. Continue up through the forest (
3) to an area where the trail is a bit difficult to follow over and around some rock slabs -
4. Near 11,400', leave the trees where you have a great view of the two streams that flow down the slope below Twin Lakes -
5. Follow the trail north up the slope and cross the first stream at 11,700' -
6. Immediately after the crossing, climb steep terrain for 300' before the trail angles right and the slope eases. Cross the second stream near 12,300' and continue toward the top of the slope -
7. Near 12,500', arrive at the south end of Twin Lakes -
8.
Off to your left (west), much of Mt. Eolus is in view -
9 is a high-angle view of the remaining route. From the flats before the lakes, locate trail to Eolus and hike below some cliffs -
10 and
11. Follow the trail southwest toward the end of the basin below Eolus' east face -
12. Continue above 13,000' as you approach the area where you'll climb out of the basin. Beyond some angled slabs, to your right, there's a ramp/ledge that climbs northeast out of the basin -
13. The ramp is difficult to identify until you are near the base. Continue over some low-angle rock slabs to reach the base of the ramp. Studying
13 will help you identify this area and avoid turning right too early. Above 13,400', reach the entrance to the ramp -
14. Turn right and climb northeast on the wide, Class 2 ramp -
15. There are a couple of sections that require careful movement across angled slabs but the difficulty should not exceed Class 2. At the top of the ramp, continue north on easier terrain to reach a flat area, east of the connecting ridge between Eolus and North Eolus. To your right, is the high basin between North Eolus and 13er Glacier Point.
Your next goal is to gain the Eolus-North Eolus ridge to the west -
16. Locate a notch in the ridge just above a short, green gully. It's best to hit the ridge at or near this notch. While there are several ways to reach the ridge, the most direct approach is to climb the green gully -
17. Some easier terrain is off to the right, but it requires zigzagging on angled slabs. After some brief Class 3 climbing, reach the notch near 13,850' -
18. From here, you have an interesting view of the remaining route to the summit -
19. Turn left, climb over a bump on the ridge and reach the "Catwalk" which is a narrow section along the ridge to Eolus. Most of the Catwalk is Class 2 but there are a few sections which require some easy Class 3 moves to overcome small dips along the way. Carefully scramble onto the Catwalk and continue toward Eolus -
20 and
21. After the Catwalk, reach easier terrain below the final summit pitch -
22.
The remaining 250+ feet to the summit requires plenty of route-finding and Class 3 scrambling. The northeast ridge is directly above but the easiest route to the summit is by climbing the east face, just left of the ridge. Turn left and traverse under rock walls on the east face -
23. After passing below the walls/cliffs, begin climbing through ledges -
24. Zigzag up the without going too far to the left or right. As you climb higher, the terrain gets steeper, but still Class 3. Even with dry conditions care must be taken on the narrow ledges -
25 and
26. Gain the summit ridge (
27) and scramble over to the top -
28 and
29.