I planned this walk as a bit of an exploratory wander and Max S walked with me.  We left Canberra at 7am and drove to the Orroral Tracking Station car park.

The main feature of Cotter Rocks is identified as Split Rock Pinnacle in ACT Granite, p 193.

Walk

We were walking by 7.45am and covered the 2.6km to the bend in the Granite Tops Walking Track in 40 minutes.  Across James Creek was a bit steep, so it made sense to go on another 270m to opposite the side creek coming in.

We crossed James Creek, plenty of water flowing after the heavy rain of the last couple of days.  With the unnamed creek now to our south providing a bit of a boundary guide, we headed due west to the source of Prarie Dog Creek.  I learned a few navigation lessons this day.  The first was not to correct planned legs on the fly.  For example, I had a bearing of 243degM prepared to get from the bottom bend in the Granite Tops Walking Track to Prarie Dog Creek.  When we went on a further 270m before leaving the track, I just tried to make a guess at varying the heading.  I should have stopped and remeasured on the map.  The second lesson was that sources of creeks (the end of a blue line on a map) don't make recognisable targets on the ground.  A GPS check showed that we missed the end of Prarie Dog Creek by 100m, but it was all just a watery swamp, churned up in places by wild pigs!

I did poorly on the next leg too.  The plan was to go to the source of Sawpit Creek, but the view SW towards this objective and on over to the top of Rendezvous Creek confused me.  As well, the going south west from Spot Height 1465 was pretty rugged, so we erred to the west.  We crossed Sawpit Creek about 400m north of its source, climbed up the ridge the other side and stopped for morning tea at 10.10am.  The 2.7km of bushbashing from James Creek had taken 1 and a half hours.

The back of Cotter Rocks was in view, so with visual clues we formed a new plan to contour round the back of a couple of unnamed creek systems, then head north west to the source of Rendezvous Creek and so across the saddle and climb Cotter Rocks from the ESE.  We passed through a massive rock shelter at Spot Height 1391, then across the source of Rendezvous Creek.  The creek looked quite benign at this point.  With Cotter Rocks in view, we made a direct line for it, reaching the top entrance of Split Rock at 11.35am.

We wandered through the split, Max not having been here before.  Something I'd not noticed on my previous trip was a brass plaque glued to the side of the split with "Ken & Kev 2003 ANU" - expensive graffiti!  We had lunch on the rock shelf to the west of the split and enjoyed an hour of the magnificent views.  The navigation pressure was off now; just the long trudge back to the car.

To the north Mt McKeanhie was clearly visible, with the unique rock stack to its south east (is this Dutchie's Peak?).  Closer were the rocky ridges above Pond Creek and closer still could be seen the AAWT winding down from Cotter Gap.  We tried to identify Coronet Peak to the SW, but with Split Rock slightly higher and the tree skeletons and rocks in the way, really had to imagine where it was.  Not so with the Bimberi peaks of Mt Namadgi and Mt Kelly rising to the south.

We headed down at 12.25pm.  It took 20 minutes to cover the 0.65km down to the AAWT.  A small rock cairn marks the spot.

8.6km of AAWT and Cotter Hut Road took 2 hours to return to our start point.  We detoured onto the Orroral Valley grasslands for the last km or so, to give our feet a rest from the hard fire trail.  Hundreds of kangaroos, just about every female having a small face peering from her pouch, or else a pair of small back legs waving in the air.

Time:  7.45am - 2.55pm, with 1 hour 15 minutes of stops.