summit cairn
  the Mount Sonder summit trail actually ends at the second highest point of the massive, the true summit of Mount Sonder being just northeast to this point and is marked by a trigonometric station; to get to the true summit requires a dangerous traverse across a steep broken col which connects the two points and takes about 1.5 hours to complete  
  Mount Sonder, West MacDonnell National Park - 30th September 2006