I did this walk solo.  Drive from Weston Creek via the southern suburbs through Tharwa.  Turn right into Orroral Road just after the top of Fitz's Hill and drive to the former Orroral Valley Space Tracking Station.  All sealed road, about 50 km and 1 hour's drive.

This walk is number 17 on the Namadgi National Park map, Walks on fire trails.  It is rated as 19 km circuit (1 day), but can be completed a little quicker than that if so desired.  The walk is also number 11 in Graeme Barrow's Namadgi and Tidbinbilla Classics: Tough Bushwalks in Canberra's High Country, rated 16.5 km, time 4 hr 30 min and category moderate.

Leaving the former Orroral Valley Tracking Station car park, I walked up towards the magnificent toilet block and then to the walk register.  The gravel path leads over a wooden bridge and on up to meet the Cotter Hut Road.

Easy walking along this fire trail in the timbered country on the edge of the Orroral Valley.  After around 4 km there is a bend in the road and a climb up away from the valley.  Pass the weather station in the bush on the right, cross Prarie Dog Creek and continue along Cotter Hut Road past where the Australian Alps Walking Track leaves it on the left.

The junction of Smokers Trail with the Cotter Hut Road was marked by a new direction sign fastened to a very black and burnt post.  Turn right onto Smokers Trail which parallels Sawpit Creek and crosses it about half way back down to the open valley.

The next junction is that of Smokers Trail and the Orroral Valley Walking Track.  Smokers Trail leads on up the Orroral Valley and up to the Corin Road.  On this occasion I turned right again and out onto the Orroral Valley.  Sawpit Creek is again crossed and then the open grasslands of the valley are walked.  Good views to the tors on the north-eastern valley rim and the rocks 'behind' the tracking station.

All in all, a very pleasant stroll.

Distance: 18.1km  Time: 8am-11.50am, with no stop.