West Eolus (13,740') is a huge fin of decomposing garbage that occupies the ridgeline west of Mount Eolus, separating Chicago Basin from upper New York Basin to the north. It is a remarkable feature of some mountaineering interest, with a gravel yield typical of area peaks. It is rumored that a Class 3 - 4 route exists on the southeast face and east ridge.

Ride the D&SNG train to Needleton, and hike 6.5 miles in to Chicago Basin. Alternatively, hike ~15.5 miles from the Purgatory Trailhead. Other creative and likely painful approaches exist from Vallecito Reservoir, Hunchback Pass, New York Basin, etc.

5.5 miles up Chicago Basin from the Needleton/Purgatory/Cascade trail junction abundant campsites may be found in the trees just beyond an open meadow at 11,000'. The creek draining the basin west of Mount Eolus intersects the trail just beyond the trees.

Leave the trail on the west side of this creek, and hike northwest up the ridge bordering the creek. Follow well-traveled game trails up this ridge, enjoying scenic views into the massively eroded creek bed, staying out of willows to the east, and navigating a few easy cliff bands.

At 12,200', a few game trails contour north off the ridge and into the high basin below West Eolus. The best trail is located up the ridge another 150' or so. Either way, head north into the basin, crossing another eroded creek bed.

When the game trails peter out, keep hiking north towards the saddle on the east side of West Eolus (this is the West Eolus-Mount Eolus saddle). Gain this saddle, and identify the game trail entering the big ledge beneath the south face of West Eolus. Routes begin on or near this ledge.