Start at the carpark at the end of Lewis Road. A gate with a “Mundy Regional Park” sign marks the start of the Whistlepipe Gully Walk trail. Follow the wide trail eastward along the south side of the stream. Just before reaching a small concrete bridge across the stream, turn right (at ‘1’) onto a smaller foot-track which climbs a short way up the hillside and over a granite outcrop before returning to the stream bank. – Beneath the granite outcrop you will see the ruins of the house built in the 1960’s which straddled the stream course and used the granite rock faces partly as walls. (See “Mythic houses…” under Other info.). Continue along the south bank of the stream until ‘2’, then cross the stream to the north side via the wooden bridge. Follow the wide and pebbly track steeply uphill, ignoring side tracks on the right at ‘3’ and ‘4’. Meet Ozone Road (at ‘5’). Follow the sealed road initially westward, around the hillside (near the top of the Scarp) for a total of about 1km, getting excellent sweeping views across the coastal plain to Perth and the coast. The road curves northward to ‘6’. (Ignore the side road, Prospect Court, on the right.) Veer NE into Panoramic Terrace (at ‘8’) and after less than 100m turn left (at ‘7’) to head NW along a dirt track which meets a junction with another track after 200m (at ‘8’).
The section of the walk, from waypoints ‘8’ to ’17’, now follows much of the West Terrace Walk Trail, but in reverse direction to the purple markers. – At the track intersection at ‘8’ take the northward track and soon descend quite steeply downhill to a T-junction with another track near the south bank of Crumpet Creek (at ‘9’). Take the right fork and cross the stream over a culvert (at ’10’), then follow the track steeply uphill to meet another T-junction (at ’11’). Again take the right fork which heads initially downhill then up the valley. Ignore t vehicle tracks entering from the left at ‘12’ and ’13’. Re-cross the creek at a bridge (at ’14’). Immediately after crossing the stream the vehicle track on the left, initially following the south bank upstream then veering southward through a track junction at ‘15’ and climbing steeply uphill (past houses on the left) finally reaching a T-junction (at ‘16’) near the edge of the flatter, lateritic plateau surface at the top of the Scarp. Follow the track approx. SW around the plateau margin through forest to another T-junction (at ’17’). Turn left to follow the track a short distance uphill to meet the intersection of four sealed roads (at ’18’). Veer left (eastward) onto sealed road and within 50m reach the corner of Prospect Rd and Ozone Tce. Turn right (south) onto Ozone Tce, with the bushland of Mundy Regional Park on your left. Within 100m (at ‘20’) turn left onto a vehicle track to enter the bushland (initially mainly parrot bush and scattered marri trees). After ~50m (at ‘21’), where the vehicle track curves to the left (ENE), take the minor sidetrack on the right which connects to another vehicle track at ‘22’ within 30m. Turn left to follow this vehicle track ENE to a junction at ‘23’. Turn right to follow a vehicle track southward to a junction at ‘24’. Veer right and immediately locate another track entering at ‘25’ (A small orange boulder sits at the right side of the track entry.) Take this entry to head initially southward and then SE down the hillside through slightly more dense forest. Pass through a track junction at ‘26’ and at ‘27’ locate and follow a minor track more steeply down the hillside, meeting a wide, unsealed vehicle track (an extension of Orange Valley Rd) at ‘28’. Turn right onto this track and at ‘29’ re-cross Whistlepipe Gully stream by the wooden bridge. Then, within 20m, locate and follow a minor foot-track which veers left off the vehicle track to head SW up the hillside toward the top of the Scarp, initially passing through heathland and then into young jarrah forest with an abundant understorey of Winged Wattle (Acacia alata). Meet a vehicle track at ‘31’ and turn right to follow the track approx. SW (via ’32’ and ‘33′) along the hillside with pleasant valley and Coastal Plain views through forest and across open heathland. Take a left branch of the track (at ’34’). The track climbs steadily and veers left (ESE) to enter forest (about ‘25’) toward the top of the Scarp (near the end of Ashurst Drive, an alternative access point). Then turn right at ‘36’ near the wireless station and old house ruins and descend toward Lesmurdie Brook. After the track turns SW along the valley slope (at ‘37’), take the next track branch on the left (at ’38’) to cross the Brook and then turn right (at ’39’) to follow the south bank of the Brook downstream to Lesmurdie Falls picnic area (at approx. ’40’; toilets, picnic area and carpark nearby). Continue on along the Falls track (via ‘41’) to reach the viewing platform (at ‘42’) which straddles the Brook at the top of the Falls. There are good views SW down the Lesmurdie Brook valley to the Coastal Plain. Follow the track SW along the steep south face of the valley (via ‘43’) and at a track Y-junction at ‘44’ veer right to follow the track downhill to meet a trail (at ’45’) along the south bank of Lesmurdie Brook. If time and energy allows, as an addition to the walk, turn right (east) to follow this trail to ‘46’ near the foot of Lesmurdie Falls (especially worthwhile in winter-spring when the Falls are in full flow). Then follow the trail west to reach a carpark at ‘47’ at the end of Palm Terrace (a sealed road). Follow Palm Tce for 300m, then turn right (at ’48’) through the gate to follow the vehicle track (Waterfall Rd) initially NE along an old fenceline, then veering east and uphill before crossing a stream gully (at ’49’). The track then climbs quite steeply northward around the hillside to meet T-junction (at ’50’). Take the left fork and follow it downhill. At ‘51’, where the vehicle track veers westward, locate and follow an old foot-track on the right which heads northward to meet Lewis Road at ‘52’ after about 300m. (Note: There is a Shire of Kalamunda track sign on a marri tree just past the track entry but this old track is not maintained and little used, so may be a little challenging to follow in places. Alternatively you can stay on the vehicle track after ‘51’ to meet Lewis Rd within 200m.) From ‘52’ just follow Lewis Rd for ~100m to return to the Start point (‘53’) at the Whistlepipe Gully carpark.