At 1,171 metres, St Mary Peak is the highest point in the Flinders Ranges and stands on the northwestern rim of Wilpena Pound. The approach from Wilpena Resort follows the Wangara Lookout trail before climbing steeply up the quartzite rim. The full return walk is about 21 kilometres and takes eight to ten hours; most people start very early to avoid the midday heat.
The views from the upper slopes are sweeping: the interior of the Pound below, the Edeowie Creek valley to the west, and on clear days the salt lakes shimmering on the plain to the east. Yellow-footed rock-wallabies are sometimes seen on the scree slopes. The upper section above the treeline is exposed and rocky, and the route is marked with cairns rather than a constructed path. Bring plenty of water — there is none available on the mountain.