ApproachThis is a 2500’+/- ascent day. Follow the drainage on the left hand side (northeast) via a faint animal trail. You are setting a due north course and soon will find yourself further to the left of the drainage which has now turned into several waterfalls. No worries, continue due north meandering through the thin forest using clearings whenever possible and ascend any options to your left, but the most efficient approach is to wait until you are almost above tree line before ascending the steeper slopes on climbers left. Once above tree line you will find short cropped high alpine flora and be in full view of Mount Arethusa’s southeast to northwest ridge.
Route DescriptionContinue on soft ground as far as you can before beginning your ascent of the large talus field aiming for the southeast ridge (ascent route drawn on top photo on main page). You will observe several steep walls at the top of the ridge. Your objective is not to circumvent them to the right, but rather to angle left working your way through breaks in these features until you are at the south end of the largest ridge wall. Ascend climbers right to the top of the ridge and continue north along it on the east side regaining the top of the ridge when the east side starts to lean eastward.
Soon you will come to the crux of the ascent which is a relatively tame, but somewhat exposed, chimney. Descend this chimney and immediately traverse back to the west side of the ridge and continue your ascent from there, staying on west side ledges virtually to the summit. Mount Arethusa’s summit did not have a register in 2005. The views are vivid via the Royal group to the west, particularly Mount Sarrail. This is also an optimum summit to scout out the scramble route up Mount Rae to the north.
Now for the tricky part. There is an optional descent. The guide book, and I concur, suggests that this descent route must be snow free. On ascent, I was not positive which steep contour offered a viable descent, therefore, I could not determine if it was free of snow or not. I have marked the proper descent route on a photo included above. You need to determine if it is snow free or not on your ascent as you won’t get a view from above. I descended this contour rock band chocked full of snow and ice and the experience made for an alpine descent, not a scramble.
Descend the summit to your left for a few meters working down ledges until you can turn back right, north/northwest. Continue across a few ledges and talus aiming for a col between the summit and a steep buttress to the northwest. This is your optional fast descent route. Due to snow in the col, I down climbed some slabs into the steep gully. I then moved in and out of snow, sometimes downclimbing snow and ice straight away, sometimes using the slabs to skiers left, sometimes using the holds on skiers right. In the end, I was damn glad to get out of this very narrow and steep contour band. This descent in these conditions took me considerably longer than if I had returned the ridge. If it is dry, I imagine it could go very fast, but beware of several water worn areas that could prove dangerous. Once down onto the large talus, just return to the high alpine flora and small tarn to the south and eventually work your way back to the animal trail on the north bank of the Arethusa Cirque drainage.