From the start point (at waypoint ‘START’ point), head westward along Summer Track (vehicle track). The track runs along the southern side of the Serpentine River valley floor, passing through lowland heathland and some open wandoo woodlands. It is generally less than 200m south of the Serpentine River course. The track soon crosses a low lying area. This is often a little flooded in winter in winter-early spring and may require some shallow wading (or deviations to slightly higher ground to help keep dry boots). After 1.7km along the track, where another stream course crosses the track at ‘1’, veer left to head SW off-track along the open valley floor, then enter the forest at ‘2’. Continue SW-ward uphill through open jarrah forest to ‘3’, then veer west to cross a narrow ridge (at ‘3-1’). Descend westward down an outcrop on the western flank. At the bottom of the outcrop you will need to patiently pick your own least scratchy route through a 30m wide belt of Prickly Moses (Acacia pulchella) to reach a small gully at ‘4-1’. Turn right to follow this downstream a short distance to ‘5’ where the stream course drops across an area of granite boulders and outcrop, forming pleasant cascades and small pools when the stream is flowing after winter rain. Then head SSW up the gentle hillside. Reach the foot of a granite outcrop at ‘6’. Climb the rock slope via ‘6-1’ and at ‘7’ turn sharply right to follow the upper slope of the outcrop NNW. Take in the view across the surrounding landscape including to Mount Cooke, 15km NNW. Veer left at ‘8’ and pick an easy way uphill through an initial belt of quite dense fringing shrubland to re-enter the open forest. Head initially westward to ‘9’ and then NW to reach another outcrop. Again, take in a good view from the high point of the outcrop to Mount Cooke again, and also to Mount Solus (15.5km WNW), and to Boonerring Hill itself (3.5km south). Then turn sharp left at ‘10’ to descend SW, initially through scratchy shrubland, and cross a gully at ‘10-1’. Cross an overgrown old vehicle track at ‘11’ then veer SSE around the hillside. Cross a smaller gully at ’11-1′ and climb through forest and some shrubland to a smaller outcrop at ‘12’. Cross the outcrop along slope to ’12-1′, then continue ESE gently upslope through forest. Veer right at ’13’ to head SSE across the gentle hilltop. Cross a slight saddle at ’13-1′ and continue SSE, climbing back up to the crest of a ridge at ’14’. Veer left (SE) to reach at ’15’ a narrow outcrop along the SW flank of the ridge crest. Follow the outcrop SE along the ridge for almost 250m. Bypass a patch of shrubland via ’15-1′ and ’16’ then veer right (southward) and descend (via ‘16-1’) to an outcrop on the SW flank of the ridge at ‘17’. From here there is a view southward to Boonerring Hill. Continue southward into open jarrah forest and along slope, crossing a stream course at ‘17-1’. Cross another narrower, deeply-incised gully at ‘17-2’ and continue SSW upslope to reach the foot of another outcrop after ‘17-3’. A stream course just to the right drops quite steeply northward from the outcrop into a narrow gully draining northward. Find an easy way through a belt of fringing shrubland to reach ‘18’ on an upper outcrop area; then veer left (SSE) gently upslope across the outcrop and through another small patch of shrubland to reach an upper granite slope at ‘18-1’. Follow the outcrop gently upslope to 19′. From here there is a good view across the head of a valley to the granite dome of Boonerring Hill, only 650m SW. This is also just a little over the halfway point on the walk and makes a good spot for lunch and/or a rest stop. Climb through fringing shrubland via ‘19-1’ to ’20’ which is on the crest of the ridge. Veer left to head SSE-ward along the ridge to ’20-1’ then continue southward along slope to meet the Bibbulmun Track at ‘21’. Turn left to follow the Track up a narrow ridge through wandoo woodland for 300m. Then leave the Track at ‘21-1’ (where it veers sharply left around the west side of the Boonerring Hill granite dome), and continue straight ahead on a spur track which heads up to the southern edge of the rock dome and provides access to the summit area. (Or see Option below at ‘21-1’ to bypass the full summit traverse). Turn sharp left at ‘22’ to clamber up the gentle rock slope onto the summit area of Boonerring Hill and to the cairn located near ‘22-1’ (elevation 533m). Take time out to wander around the summit area to take in the magnificent views in all directions across the surrounding Darling Range plateau. Some of the landmarks include Mount Solus (22km NW), Mount Cooke (22km NW), Bannister Hill (14km SE), Kimberling Hill/White Horse Hills, 4.5km SW), and Bowerling Hill (6.5km WNW). Descend northward-NNE from the summit via ‘22-2’ down the steepish northern slope. The descent is not difficult and is only 60m of elevation loss, but is safest to stick to a strip of fractured and partly vegetated rock which provides a reasonably easy route down and avoids likely treacherously slippery patches on the smoother rock surface. Pass through a narrow patch of forest on a saddle area at the foot of the granite dome and reach a smaller outcrop at ‘23’ from where there is a good view back to the summit area. Cross the outcrop northward to rejoin the Bibbulmun Track at ‘23-1’. Turn right to follow the Track NE-ward for 1.8km. Then veer left off-track at ‘24’ just before the Track crosses a stream. Follow the west bank of the stream course northward and cross the stream at about ‘24-1, then re-cross it within about 150m, at ‘24-2’. Then continue NNW down the pleasant valley via ‘24-3’, picking an easy way through or around patches of shrubland. Wandoo trees line the banks of the stream course. Veer right (northward) at ‘25’ and re-cross the stream course again through shrubland at ‘25-1’. Head NNE-NE around the hillside, via ‘26’. Cross a broad, near flat saddle area at ‘26-1’ and veer left (northward) at ‘27’ to descend to the valley floor (via ‘27-1’). Bypass shrubland fringing the stream course, then veer right (NNE) at ’27-2′ to rejoin Summer Track about 250m from the start point.
Option to bypass the summit traverse (from ’21-1’): If preferred, especially in wet weather, you can stay on the Bibbulmun Track from ‘21-1’ and rejoin the described route at ‘23-1’. Alternatively, to avoid the steepish northern descent from the summit, consider making a return trip to the summit on the spur track from ‘21-1’ which adds only 250m to the total walk distance. The spur track provides a gentler and safer wet weather return route from the summit.