17 March 2015
We start at the top of Hall Village at the rebuilt (in concrete blocks) Anglican
church of Saint Michael and All Saints. It’s a real country church with its detached demountable room for a church hall, detached bell-tower, stained-glass window, access ramp, water tank, and its post-and-rail, bush-garden and wooden-bench rest area (winner of Australia’s Open Garden scheme community grant 2000), dedicated to the Hall Pioneers.
The trail proceeds along a quiet 
street lined with solid old houses and well-established gardens up to the One Tree Hill entrance to the trail, where the grassy slopes, cleared for grazing long ago, have been planted recently with saplings with barriers around them for protection from the kangaroos. We meet two early walkers returning to Hall Village.
As we continue along a ridge beneath the rounded grassy hills, views of the whole
of Canberra and beyond unfurl: the Brindabella range, Belconnen Town Centre and suburbs, Black Mountain with two hot-air balloons soaring in the sky above it, Parliament House, the new Gungahlin suburbs under construction, and away to the south we can just make out the white Lovett Tower at Woden and to the east, the wind turbines on the hills at Tarago.
Approaching One Tree Hill we enter re-generated woodlands of magnificent red and yellow box teeming with warbling magpies, whistling thornbills, twanging weebills, squabbling chuffs, chirruping willy-wagtails, piping parrots. A young wallaby hops away into the woods above us; below, a swamp wallaby is nearly camouflaged among the trees. The wide valley is densely wooded: a reminder of what this area must have been like two hundred years ago, and may be again.
On Carol’s maps certain sections of this part of the trail are marked as ‘difficult’, which at first we find strange, because for us, they are all downhill. Then we twig: we are walking in a clockwise direction, whereas the maps indicate the sequence of sections in an anti-clockwise direction. The Centenary Trail signs, however, work both ways, and unlike some of the sections we have covered previously, today they are impeccable for the whole twenty-six or so kilometres. This is probably largely due to the fact that it is all bushland, and no developments have sprung up between when this part of the trail was plotted and now.
Shortly after we leave One Tree Hill (on which there are more trees than one) we take our first break on a switchback slope into a gully which has been invaded by wild rose bushes festooned at this time
of year with red hips. It’s obvious why there are so many briars: parrots feeding on the fruit fling the seeds around with gay abandon.
Now we stop to admire a magnificent solitary tree set in rolling grasslands. And now we are in a tangled tapestry of trees growing at different angles, spindly branches and leaves intersecting, cast-off branches littering the forest floor. The trunk and branch of an ancient fallen specimen arch over the trail; its suckers are pushing their way back into forest. A cyclist coming from the opposite direction tells us we are coming to a very pretty section and to watch out for the sheep.
We enter another extensive grove of yellow box with their lovely yellow and grey 
trunks; and on one of the switchbacks in the trail circumnavigate a gallery of cairns built from big and small yellow limestone rocks lying all about. We each add a stone to one of the smaller cairns as we follow the trail around.
The track meanders through uneven terrain, zigzagging along crests and slopes following the watershed that forms the northern border with New South Wales. Rainfall on the ACT side flows into the Ginninderra Creek catchment then into the Molonglo River, rain on the NSW side of the fence flows toward the Yass River. Where the bearing of the border changes, the surveyors arranged rocks to form lock spits, which are still clearly visible wherever the fence on our left changes its bearing. Once the border was determined in 1910, property owners were advised of changes in land tenure conditions. On the NSW side they retained freehold title; on ACT side holdings would be eventually resumed by the government.
On our right are chicken wire fences with lines of barbed wire along the top, a barrier which evidently makes no impression on the kangaroos, judging by the bulges and gaps at the bottom of the fences and the long imprints of kangaroo tails on both sides. An enormous kangaroo keeps an eye on us from a few hundred metres away in a fenced field, then jumps the fence and is off out of our sight. We are passing along part of Elm Grove Station, the only remaining working rural property in the Gunghalin area. Here we come across the large woolly sheep the cyclist told us about: the sheep watch us nervously until we are about a hundred metres away, and then clatter off, dislodging the stones before they disappear among the rocks and trees.
At last we reach the Northern Border Campsite, a well-maintained fenced area offering a drop toilet, picnic tables, a water tank and covered shelters, but no actual campers.
Below Oak Hill spreads the new suburb of Bonner, the most northerly suburb of Canberra, and still in development.
A noticeboard provides some history of Elm Grove Station and of the survey led by Charles Scrivener in 1910. It also provides a panorama of the whole of the Australian Capital Territory, its mountains, town centres, nature reserves and landmarks. It lists the many native plants of the area: snowgum, stringybark, scribbly gum, bundy, brittle gum, peppermint, apple box and wattle. The dense woodland we admired from One Tree Hill, we discover, was a eucalypt plantation established by the ACT government in the early 1990’s to provide domestic heating in the ACT. Fortunately for the trees and the Territory, that policy has now been abandoned.
Mulligans Flat, today’s destination, was in the past a quarry where the Indigenous inhabitants sourced stone to make implements for finding and preparing food for cooking and for making tools. Descending Oak Hill towards Little Mulligans Flat, we notice several Golden Sun Moths that inhabit this area; more of them flitter among the reeds in the run-off tanks beside Mulligans Flat Road. These moths are rare and need protection; we feel privileged to have seen so many.