The Trough Waterfall (or Secret Woy Woy Waterfall as it’s sometimes called) is no longer really a secret, having become a Central Coast Instagram hotspot over the last couple of years… While this is a popular attraction, combining the waterfall with Mount Wondabyne makes a very enjoyable half-day bushwalk that takes in a few scenic sights. The bushwalk starts from Woy Woy Road and starts with the somewhat uninspiring Tunnel Firetrail, which passes a flooded quarry before entering Brisbane Water National Park.
There’s a view of Mount Wondabyne in the distance, which at 251m in height is the highest point in Brisbane Water National Park.
Trough Waterfall (aka Secret Woy Woy Waterfall)
After 1.9km there’s a four-way junction, and we turn left off the Tunnel Firetrail and onto another (unmarked) firetrail, which gradually descends. The easy way is to just follow the firetrail down to the end; instead we push through some thick scrub to the south of the trail, to reach a small creek. We then follow the creek downstream past some nice waterholes and small cascades.
We continue down the creek until it reaches a rock platform and plunges over a sheer cliff face. Peering carefully over the edge of the cliff, you can see the Woy Woy Waterfall below.
On the rock platform above the waterfall are a number of Aboriginal axe grinding grooves and water channels.
While the infamous Secret Woy Woy Waterfall / Trough Waterfall is directly below us, unless you’ve got abseiling gear you need to follow the top of the cliff-line in a southerly direction. After a couple of hundred metres there’s a rough track that drops down the side of a steep rock face.
Continue down along the cliff, and you’ll soon see the Woy Woy Waterfall directly in front of you. It’s literally a trough at the base of the waterfall, which captures the water from the small creek. The trough may have been built during the construction of the railway tunnel in the early 1880s as a source of fresh water for builders, or during the operation of the Woy Woy Basalt Quarry in the 1930s. The water is pristine although it’s a bit tricky clambering into the reservoir. The Trough Waterfall is becoming a popular swimming spot – but note that it may not be structurally sound and could one day collapse (hopefully without anyone in it)!
We return the same way from here, back up to the top of the cliff and up the firetrail to the junction with the Tunnel Firetrail.
Once back at the junction, we turn left to continue down the Tunnel Firetrail. We pass another locked gate, which may (many years ago) have marked the boundary of Brisbane Water National Park – but it’s now well within the park boundaries.
We make a short detour (or bushbash) to a rocky outcrop off the firetrail to have a look at an Aboriginal engraving of a kangaroo, which has been engraved in a shallow pool.
Just over two kilometres along the Tunnel Firetrail brings us to the next (signposted) junction, where we turn right onto the Mount Wondabyne Firetrail. This section of the walk is also part of the Great North Walk (GNW) route, so there are frequent GNW markers. After just under a kilometre of easy walking we reach the Mount Wondabyne bush camping site, which also has a pit toilet.
Just beyond the campsite is a side-track up to the Mount Wondabyne summit and trig point. The short but fairly steep track climbs up to the rocky peak, which is fairly clear of trees and offers great views.
(If you’re doing this walk in the afternoon and don’t mind completing the loop at night with a headtorch, plan to get here just before the sun sets for some stunning Mount Wondabyne sunset views.)
Just after the junction with the trail up to the Mount Wondabyne summit, the Mount Wondabyne Firetrail turns into a bushwalking track. There’s some views out over Brisbane Water National Park.
It’s about 1.5km along the narrow bushwalking trail, which is a nice change from the firetrails. As the trail descends the northern flank of Mount Wondabyne there’s a few steep sections, and it crosses some rock platforms.
A few of the rocks have a very oily substance seeping out of them, which I’ve seen a few times on recent bushwalks. It’s not oil, but iron bacteria which occurs naturally. Bacteria which live underground feed on iron-rich water, creating an orange/rust coloured slime which looks very similar to an oil spill. A very wet fwe months may have resulted in more occurences of this natural phenomenon.
The bushwalking track meets the Mullet Creek Firetrail; we leave the Great North Walk route and continue along the Mullet Creek Firetrail until it meets the Tunnel Firetrail to complete the loop.
Getting to the Trough Waterfall and Mount Wondabyne
The loop bushwalk starts on Woy Woy Road with the signposted Tunnel Firetrail. It’s about 15min south of Gosford and an hour north of Sydney. There’s limited parking at the start of the trail, and more parking along the shoulder of Woy Woy Road.