The Timberline Loop is a fantastic route that utilises both old logging roads and the Sidings Rail Trail that make for a delightful walk or cycle in this heavily wooded area.

The Timberline Loop makes a fun half-day mountain biking ride or pleasant 2-day hiking trip.

The Timberline loop, when travelled in an anti-clockwise direction, follows the Munda Biddi Track (this section is also known as the Sidings Rail Trail) north until it heads south again along the Timberline Trail. You can ride it in the opposite direction, or skip the Munda Biddi part completely by riding out and back on the Timberline Track.

The Timberline Trail mostly follows the path of wood powered steam driven locomotives which hauled logs from the forest to the Barrabup Mill and later Nannup Mill. When the government opened the railway between Busselton and Nannup in 1909, the Kauri Timber Company established the Barrabup Mill on the banks of St John Brook near the Workers Pool camp ground and built a connecting railway to Cambray Siding (on the government line).

If you ride the track anti-clockwise, the first half of the route follows the Munda Biddi Trail. It’s a wide, smooth, and mainly straight gravel path. The elevation gain is so gradual you may not even notice it. Keep a look out for some old telegraph poles (marked on map) and sections of the railway line that have been kept intact.

At the northern extreme of the loop you turn left and bear south along the Old Timberline Trail. The next 8 or so kilometres is on a good gravel road through beautiful forest and bush beside the pretty St Johns Brook. It’s a little hillier here. You’ll pass the Sleeper Hewers camp site then a spectacular ruined railway bridge from the days of logging 100 years ago. Note: that the Sleeper Hewers camp has a hut with bunk beds for 8 people, a rain water tank, toilets, a picnic table and access to a swimming hole on St Johns Brook.

The track passes by Barrabup Pool (a great place to swim) then Workman’s Pool before heading back to Nannup on mostly fairly easy single track.

A bit of History:
The Barrabup Mill employed 150 men in its heyday and could produce 30,000 super feet of timber per day. A “super foot” is a unit of timer volume measurement – it equals the volume of a one-foot length of a board, one foot wide and one inch thick. The timber town had a school, doctor and nurse, boarding house, billiard hall and post office. Company railway lines criss-crossed the bush bringing the highly prized Jarrah logs to the mill.

When a new mill was established in Nannup in 1925, the Barrabup Mill and timber town were closed. Almost everything was dismantled and transferred to the new mill. The Old Timberline Trail follows the path of some of the Kauri Timber Company lines. At Cambray Siding, the trains topped up their water from a water tank at the siding before continuing on to Busselton jetty