Serpentine - Karnet Rock Walk (Walk #13)


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On this page:  

1) Walk map - Shows route and waypoint locations

2) Photo from walk  (also see Photo Galleries)

3) 3D map view

4) Google map & Satellite imagery

5) Route profile

6) Walk description

7) Waypoint listing and grid references


 Walk map  Photo
Click on map for large version.

Rock pool on Karnet Rock and view to distant

 Mounts Randall, Cuthbert & Vincent, Nov. 2002.

Click on photo for larger version.

More photos.

       3D map view




  Google Map

Using this map.



 Additional Satellite Imagery

Click here

for larger frame Google Maps image

of the walk area.

-Use zoom bar

for road details.

For Google Earth  users

Step 1: Left Click here

For fly-in to waypoints and route

 on image of the walk area.

Or Right Click to

 "Save Target/Link As..."  kml file.

Step 2: Left Click here

For fly-in to 3D view

 of the walk area.

Or Right Click to

 "Save Target/Link As..."  kml file.

Hint: For enhanced 3D effect, set 'Elevation Exaggeration'

in Google Earth to "3" (via 'Tools' menu, 'Options' & 'View' tab).


        Route profile



 Walk description  
Location :

62 kms south of Perth. 

Length :

15 field kms (50% off-track)

or 9.5 km short-walk option.

Degree of difficulty :

MEDIUM   (What does this mean?)

Amount of uphill walking :

360m (cumulative ascent)

GPS-preferred :


Access  :

See Google Map for start point on road map.

(Use zoom ladder for detail. Select 'Hybrid' to add satellite imagery.)

Access: Kwinana Freeway south, then Mundijong Road east to South Western Highway. Then 11 kms south on Highway, then Kingsbury Drive (on left) for approx. 11.5 kms to unmarked 'Berkeley Rd' (old dirt road) on right (1.2 kms past Karnet Prison Farm on right at end of straight stretch of Kingsbury Rd). Drive only approx. 130m down Berkeley Rd to find a suitable parking spot at the Start point. 

Alternatively, the Start point can be reached by taking the Jarrahdale Road turn off South Western Highway and then turn right into Kingsbury Drive (at end of Jarrahdale township), then follow the Drive for about 8 kms to cross Serpentine Dam wall and then a further 4.5 kms to 'Berkeley Rd.'

Important access issue:  Unfortunately entry to much of this traditional bushwalking area is now prohibited under by-laws and related policies and guidelines as it lies largely within a 2 km wide Reservoir Protection Zone ('RPZ'). Bushwalkers should not enter that area. Fines of up to $200 apply for unauthorised entry (and are recommended in Sept. 2010 Parliamentary Committee report to be increased to $5000). I accept no responsibility if users of this site ignore the restrictions and this update at their own risk. Restricted access around public drinking water source areas is intended to protect against perceived possible acute risks to water quality.

Most walks on WalkGPS lie within the outer water catchment areas, 'safely' beyond the RPZs. However, walkers need to be aware that this walk area and many others on WalkGPS lie within drinking water catchment areas. In 2007 DoW in effect recommended a prohibition of all traditional off-track bushwalking activities across the entire Perth region catchment areas covering 4500 sq km, far beyond the limits of  existing or proposed Reservoir Protection Zones(see map). By March 2008, the DoW had been persuaded to reconsider its published position. The new Policy of 2012 refrains from banning traditional bushwalking in the outer catchments. The community, including visitors to WalkGPS, need to remain vigilant to ensure that commonsense continues to prevail over regulatory zealotry. See also Home page: 'Access' and Related access issues on WalkGPS, and DOW's    "Serpentine Dam Catchment Area...Drinking Water Source Protection Plan" of 2007.

Escape route/s :

In western area, walk west via Spencer Rd (old dirt road) to meet Kingsbury Drive (at a point only 1 km west of the map edge, via waypoint '98'); OR north via old dirt road along west bank of Snake Brook and then approx. SE  along park/catchment area access road (along SW side of Pipehead Dam) to Serpentine Dam;

OR in south and east, less than 1 km through forest to Kingsbury Drive.

Main features


This walk area straddles the southeastern area of the Serpentine National Park and the adjacent State Forest (Karnet Block) and the Darling Range Regional Park in the north. It includes a gentle ascent of 'Karnet Rock' (elevation 358m) which provides excellent views NE across the Darling Range, including to distant Mounts Randall, Cuthbert and Vincent (19 kms).   Traditionally the walk area has also often been referred to as the "Three Brooks" area because of the three streams (Lucy, Bull and Snake Brooks) which drain roughly northward into the Serpentine Pipehead Dam.

Apart from Karnet Rock the route features other granite outcrops in the NW and east which also provide good views of the surrounding forest.  It also includes a few  kilometres of very easy walking along mainly old and disused vehicle tracks, plus some very pleasant on-track walking near the SW side of the Serpentine Pipehead Dam within the National Park, downstream of the Serpentine Dam picnic areas.  The off-track walking is not demanding. It includes a few small step-across stream crossings across the three Brooks, which are helped by fallen logs in two cases.  As always the heathlands around some of the outcrops provide great wildflower displays in spring.

The Serpentine Dam is well worth a visit at the end of the walk and can be reached by driving NE along Kingsbury Drive instead of returning west directly to South Western Highway. -See Access notes above.

Be aware that much of this walk is within the Serpentine Pipehead Dam Water Catchment Area. - Take special care to maintain good bush hygiene, including the usual commonsense 'restrictions' (leaving behind no rubbish, avoiding walking in the streams, and not bathing/swimming in the Dams, etc).

Future impact of bauxite mining: ALCOA plans to expand its bauxite mining within the Serpentine Water Catchments northward into the Karnet area south of the Pipehead Dam in 2013 (see image). The expansion will impact directly on the walk route on this page, and is a depressing reminder of the inexorable spread of State-condoned bauxite mining across much of the forested area of the Darling Range near Perth (See also the current expansion at Mt Solus and Worsley's future operations at Bannister Hill).

Additional maps :

WalkGPS walk map for OziExplorer users A downloadable OziExplorer format MAP file (*.map) for this walk area is included on the Maps, Waypoints & Track Files page. The zipped folder also includes the associated 'base' topo map image file, plus other attached waypoints, tracks/routes, etc in OxiExplorer file formats.

Other:   Jarrahdale  1:50,000 Sheet (CALM, 1990);

or Jarrahdale 1:50,000 Sheet 2133-3 (CALM/DOLA, 2001);

or Jarrahdale & Yaganing 1:50,000 DEC Conservation Operations Graphic (COG) map series (current) Sheet 2133-3 & 2133-2;

or Jarrahdale 1:25,000 2133-III, SW sheet (Dept. of Lands & Survey, 1984; Series R811) -available on DVD.

Other background references :

Serpentine  National Park Management Plan 2000-2010 by Dept. of Conservation and Land Management (CALM). - See pdf version which also includes all map figures.  This has summaries of the flora & fauna, geology, history, future park plans, etc.

Also, "Serpentine National Park"  article by D.Gough et al, in Landscope magazine (CALM), Vol.11, No.2, Summer 1995-96, pp.28-35.  

Water Corporation also provides a brief summary of the history and facilities for the nearby Serpentine Pipehead and Main Dams.

DEC's website also provides a brief summary of the flora and fauna, and history of Serpentine National Park.

"Serpentine National Park - Park Guide" by DEC (undated pdf; 345KB).

"Serpentine Dam Catchment Area and Serpentine Pipehead Dam Catchment Area Drinking Water Source Protection Plan" (Report # 78, Water Resource Protection Series) by Department of Water (DoW), July 2007. - See pdf version (2.3MB). Pages 42-43 are of particular relevance. 

Note: DoW's recommended protection strategy in Report # 78 intended to prohibit recreational off-track bushwalking opportunities within the entire 690 sq km catchment area, far beyond the proposed ~120 sq km Reservoir Protection Zone, and including this walk area.

Route notes :

Walk NE from the Start point on 'Berkeley Road'  for about 150m to reach and cross Kingsbury Drive. Walk around the large log (at waypoint '1' which blocks vehicle access to an old dirt road on the north side of the Drive.  Follow the road approx. north for 200m and then when the road branches to the right (at '2')  head approx. NE off-track to cross a laterite ridge and after about 250m reach a granite outcrop.  Follow the outcrop approx. northward and downslope (via '3', '4' and '5') for about 700m, partly through patches of heath and shrubland.  -There are a number of narrow but fairly dense patches of One-sided bottlebrush (Calothamnus sp.) on the outcrop that you will need to 'thread' your way through. (If you do find the shrubs are too dense here, you can instead bypass '4' by heading NW from '3' to reach a vehicle track in less than 200m and follow that to near '5'.) Near the bottom of the granite slope pick a way through a final patch of bottlebrush, then continue downslope in jarrah forest to cross a small stream (Lucy Brook, at 'STRM').  Climb approx. northward through forest (via '7') to reach the crest of another ridge (at '8') and soon reach a small outcrop (at '9'). Veer east to cross the top of a small stream gully and then (at '10') veer initially NE to follow the eastern side of the gully downhill  through woodland (via '11' and '12'). At '12' veer NE to soon cross a small creek ('CK') and meet an old overgrown dirt road (at '14').  Turn left (approx. NW) to follow the old track (via '15', '16').  In sections where the old track becomes too overgrown to follow directly, you'll need to pick out  short off-track, parallel detours.  Then meet (at 'RD') a park/catchment area access road which runs along the SW side of Pipehead Dam. Turn left to follow this dirt  road for about 3 kms (via '18'-'25'). At a couple of points (e.g. at '20') there are short side tracks/roads to the edge of Pipehead Dam which provide pleasant views of the narrow lake and surrounding forest. (The access road in places passes through small cuttings, probably following the route of a former railway dating to about 1898-1913 which ran down this part of the Serpentine valley to carry large amounts of timber extracted from the area.  The railway formation also ran part-way along the gullies of Bull and Snake Brooks.)   Where the road crosses Bull Brook (soon after '21') there is a picturesque glade of Tree Ferns (Cyathea sp.) localised around the small bridge. - These are not native to the area, but are a hardy, introduced 'weed' species from the Eastern States.  Ignore the road that branches to the right after waypt '24', but soon after (at '25') leave the road to head approx. SW off-track to cross a small stream course and in less than 100m meet an old vehicle track (at '26'). Turn left to then follow the track approx. southward (via '27' and '28') close to the west bank of Snake Brook. After '28' continue on the track for about 250m,  but then head SW and off-track to climb the hillside through forest to reach an outcrop (at '29'). Veer southward along the outcrop and then along slope through forest to another outcrop (before '30') which provides good views across the forest to Mounts Randall, Cuthbert and Vincent.  At '30' turn left (approx. SE) to head steeply back down the hillside to meet the track along Snake Brook again (at '31'). Turn left (NE) and follow the track for less than 200m, then turn right (at '32') to cross Snake Brook off-track via a fallen log. Climb the steeper slope on the east bank and then the nearby granite outcrop (to '34'). Then veer southward, initially climbing fairly steeply uphill and then along slope, crossing a series of small granite outcrops (via '35' and '36').  Cross Spencer Road (a dirt road, at '37') to near the foot of a granite outcrop and climb SW up the gentle slope of the outcrop (to '38').  Then veer approx. SE along the hillside through forest for about 500m to reach (at '39') the north edge of Karnet Rock. Climb the granite slope to the local high point (and in winter to spring a small rock pool) at 'K-ROCK', from where there is a great view again to the 'Three Mountains'. Continue south along the ridge to '41' and then turn left (east) to gently descend across a patch of rocky heathland and then through forest (via '42').  After '42' the  descent steepens a little before the route crosses Spencer Road (dirt road) and soon after crosses Bull Brook. Again the Brook can be crossed via a fallen log (at 'CKLOG') which may be partly hidden in the fairly thick vegetation along the Brook.  After crossing the Brook continue east a very short distance to meet another old dirt road. Turn right (SE) to follow the road as it curves around the valley (via '44' and '45') and then heads NE.  Downslope to the right of the road the open woodland in the valley is dominated by Bullich (Eucalyptus megacarpa), an attractive smooth-barked tree with a grey to white or pale cream trunk. On reaching a T-junction (at '46') follow the right hand fork SE for only about 100m to where the track again forks (at '46A').  Take the right hand fork again (which is quite overgrown) and follow it approx. southward for about 300m, then (when the track veers left) continue off-track southward to soon recross  Kingsbury Drive  to get back to the nearby Start point.  

Short-walk option (9.5 kms):  For a shorter walk, initially follow the route above in reverse (i.e.  '46A', '46' '45', etc) to cross Karnet Rock early in the walk. On reaching waypt '35' instead of descending to '34', continue around the hillside to '47' to meet an old dirt road (see pink route segment on map). Turn left to follow the road northward down the ridge (via '48').  Turn right at the T-junction with another old road (at '49') and head SE to cross Bull Brook at a very small waterfall ('FALLS'). Then cross a gentle ridge (via '51') and reach another dirt road (at '52').  Follow the road up a stream valley and when the slope flattens off veer left (SE, at '53') off-track to cross another  ridge (at '54') and then descend eastward to reach an outcrop (at '55'). Follow the outcrop SE and  initially downslope (to '56') and then continue SE along slope  to soon re-enter forest and meet an old road (at '57').  Follow the road southward up the hillside and continue on the road to '2' etc back to the Start point, or alternatively leave the road near '5' to follow the granite outcrop (via '5', '4' and  '3') and rejoin the road at '2'.



 Waypoint listing


Right click here and then "Save Target/Link As..."  if you wish  to download the waypoints and GPS 'track' as a GPX  file in the standard format recognised by most devices and programs including Garmin and Magellan units and GPS Mapping Software.  If you have a problem uploading the data, please feel free to contact me directly at WalkGPS rather than your users' forum!

Also see WalkGPS Maps, Waypoints & Tracks page for downloadable MAP files, plus GPX and Google Earth (KMZ) files. Also see explanatory notes on file formats and how to upload to your unit.

If you require another format you will need to convert the downloaded file using GPS Visualiser (online) or freeware such as GPSBabel.

The waypoints in the alternative listing below are given as UTM coordinates with datum to match the Walk Map. NOTE: If you wish to manually enter these into your GPS unit you must first set your unit to the correct Datum. Caution: An incorrect datum can result in an approximate 200m location error! (This is a very slow, error-prone method compared to using the above downloadable file and is not recommended.)


Route list :

Projection : UTM       Datum : Geocentric Datum Australia 1994      Zone :  50

Waypt name        Easting       Northing      Comments

START       414090  6411205  On 'Berkeley Road', 130m from Kingsbury Drive.

1           414213  6411292  Old dirt road leaves nth side Kingsbury Drive.

2           414175  6411491  Old dirt road branches.

3           414345  6411695  Near top of granite outcrop.

4           414505  6411839  On granite outcrop.

5           414340  6412022  On granite outcrop.

STRM        414645  6412409  Cross Lucy Brook.

7           414712  6412502 

8           414708  6412931  On ridge east of Lucy Brook.

9           414762  6413059  Edge of small granite outcrop.

10          414928  6413042  On SE side of stream gully.

11          415045  6413212  On SE side of stream gully.

12          415069  6413530  Cross old dirt road.

CK          415153  6413598  Cross small stream.

14          415170  6413611  Meet old disused (overgrown) dirt road.

15          414971  6413886  On old overgrown dirt road.

16          414933  6414127  On old overgrown dirt road.

RD          414960  6414292  Meet access road along south side of Pipehead Dam.

18          414602  6414063  On access road along south side of Pipehead Dam.

19          414243  6414642  On access road along south side of Pipehead Dam.

20          414086  6414663  On access road along south side of Pipehead Dam.

21          413938  6414375  On access road along south side of Pipehead Dam.

FNS         413783  6414458  Road crosses Bull Brook. Glade of Tree Ferns.

23          413663  6414940  On access road along south side of Pipehead Dam.

24          413197  6415127  On access road along south side of Pipehead Dam.

JCN         413076  6415063  Road branches.

25          412964  6415047  On old dirt road. (Begin short off-track section.)

26          412926  6414966  Meet another old dirt road.

27          412948  6414571  On old dirt road along west side of Snake Brook.

28          412613  6413936  On old dirt road along west side of Snake Brook.

29          411724  6413471  On granite outcrop.

30          411732  6413106  On south edge of another granite outcrop.

31          411867  6413021  Meet old dirt road along west side of Snake Brook.

32          411969  6413170  On old dirt road along west side of Snake Brook.

LOG         412010  6413145  Cross Snake Brook via old fallen log.

34          412100  6413153  On small granite outcrop.

35          412164  6412979  On small granite outcrop.

36          412150  6412755  On small granite outcrop.

37          412210  6412584  Cross Spencer Road (old dirt road).

38          412117  6412432  Near top of sloping granite outcrop.

39          412317  6411957  At north edge of Karnet Rock granite outcrop.

K-ROCK      412307  6411730  On northern high point of Karnet Rock.(Good views).

41          412313  6411552  On southern area of Karnet Rock.

42          412848  6411534  On old overgrown road, in forest.

CKLOG       413303  6411692  Cross Bull Brook via fallen log (may be hidden!).

44          413438  6411480  On old dirt road in upper Bull Brook valley.

45          413603  6411437  On old dirt road in upper Bull Brook valley.

46          413845  6411747  Near old road T-junction.

46A         413947  6411696  Fork in track.

END         414090  6411205  Back at Start point on Berkeley Road.


Additional waypoints on map : 

BERKRD      413967  6411254  Berkeley Road turnoff from Kingsbury Drive.

47          412372  6413133  On "Short Walk" route. Old dirt road.

48          412426  6413347  On "Short Walk" route. Old dirt road.

49          412680  6413508  On "Short Walk" route. T-junction.

FALLS       412973  6413314  Cross Bull Brook at small waterfall.

51          413222  6413452  Near ridge east of Bull Brook. "Short walk" route.

52          413362  6413257  Meet old dirt road near stream gully.

53          413565  6412900  On old dirt road, on "Short Walk" route.

54          413866  6412734  On "Short Walk" route. Cross ridge (in forest).

55          414030  6412763  Near top of sloping granite outcrop.

56          414166  6412636  On "Short Walk" route. On granite outcrop.

57          414361  6412365  On "Short Walk" route. Meet old dirt road.

58          411766  6412665  On Spencer Rd, at boundary of Serpentine Nat. Park.

60          413307  6414029  Old dirt road junction (approx.), north Bull Brook.

70          415317  6411583  Old dirt road leaves Kingsbury Drive in SE.

71          414797  6412203  On old dirt road along upper Lucy Brook valley.

80          413383  6410899  Spencer Rd (dirt road) leaves Kingsbury Drive.

90          412540  6410573  Old dirt road leaves Kingsbury Drive in south.

91          412650  6411112  On old dirt road south of Karnet Rock.

95          411732  6410464  Old dirt road leaves Kingsbury Drive in south.

96          411973  6411584  North end of old dirt road, west of Karnet Rock.

97          411385  6412390  On Spencer Rd, just west of Snake Brook.

98          411004  6412934  Spencer Road crosses another old dirt road.

TOP-PK      415187  6414260  Carpark above south end of Serpentine Dam wall.

LR-PK       415000  6414467  Carpark at picnic area below Serpentine Dam wall.

PK-TR       410953  6411233  Dirt road meets Kingsbury Drive(Nat.Park: SE cnr.)


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This page was last updated  :   24 March, 2017

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