A general view of South Crater from the summit of Ngaruhoe. Photo NC.

From the Saddle the track crosses South Crater to join the bottom of a ridge at its eastern end (in shade), which is climbed to the summit of Red Crater (visible just below Blue Lake). This is the second and last major stretch of steep walking on this route (if walked in this direction). The altitude gain is about 200 m (656').
South Crater develops between Ngaruhoe (south) and the summit ridge of Tongariro (north, here extending left from Red Crater). It is thought to be an erosional basin rather than a genuine volcanic crater.