Eyebrow Peak is the main focus of mountaineering in the group while the other peaks are "devoid" of mountaineering interest. It is part of the Main Uplift of the Purcell Range, and the tectonic movements created intense heat and pressure. The heat made the rock more elastic, and the pressure caused the rocks to be folded, faulted, and squeezed upward, forming the high peaks and structures seen today. Because the rock was mainly quartzite and was more elastic from the heat, it had the strength to prevent it from collapsing as it was pushed upwards. This led to the high rugged peaks in the area today, in which vertical relief of over 2000m is not uncommon, and helped to form the steep valleys lush with forest cover typical of the group. The largest glacier in the group is the Starbird Glacier, but there are many other good sized glaciers which emanate from around Eyebrow Peak. The rock quality in the group itself is variable and consists mainly of friable sediments which range from reasonably firm to horribly loose. History: The First Nations may have been the first to see the peaks in the group while exploring the Horsethief Creek drainage. They may have attempted to go up the Stockdale Creek drainage although the crossing at Horsethief Creek to get into the Stockdale drainage may have deterred them.
The first white man to visit the group may have been David Thompson, or Thomas Starbird. Starbird was the first permanent settler in the Horsethief Creek valley and in his travels in the valley would have seen the peaks in the eastmost portion of the group.
The first major ascent was of Eyebrow Peak in 1914 by a party that contained E.W. Harnden, one of the first climbers to venture into this area of the Purcell Mountains. Eyebrow Peak was a major prize at that time. Birthday Peak was first ascended by A.H. & E.L. MacCarthy and Conrad Kain on Kain's birthday and aptly named. Several other peaks such as Dorothy and Camp Peak were ascended by ACC parties from "Thunder Camp", the ACC camp setup in July, 1928 at the confluence of Horsethief Creek and the creek that drains the Lake of the Hanging Glacier. The other three major routes on Eyebrow Peak were also done by parties from the ACC Thunder Camp. Besides Eyebrow Peak, since then the other peaks in the group see very few ascents and the Tricorn Peaks were not ascended until 1963, while the first ascent of Stockdale is unknown. Peak So07 on the SW edge of the group above the Starbird Glacier was only ascended out of interest by a party that was doing a high level traverse from Starbird Pass to the MacBeth Group.