The Viaduct’s History
Designed by John Whitton, The Knapsack Gully Viaduct once formed part of the the Lapstone Zig Zag , which climbed the eastern side of the Blue Mountains to Glenbrook. The construction stands 40 metres high. and 118 metres long, making it an impressive structure when viewed from below. Originally used for rail transport, the bridge was modified in 1926 becoming a section of the Great Western Highway for normal vehicle use. The upgrade of the M4 however, has bypassed this section of road. This is great as it can be used for bikes, and hiking, as there are some great walking tracks nearby. This beautiful piece of construction is heritage listed.
Access to the Knapsack Gully Viaduct
Setting off from the car park at the trailhead, we found the walk to the viaduct very easy because it is flat and well maintained. From here, a steep track made of roughly formed steps descends to the base of the bridge. These are difficult to negotiate in places, but we had no issues with this because we wore sturdy footwear.
The reward for climbing down is a magnificent view of the viaduct from the valley floor, where the scale of the arches can really be appreciated. There is a canopy of vegetation, and large rocks, on which we were lucky enough to see a bearded dragon lizard sunbaking. We managed to take some great photos.
Climbing back to the roadway on the opposite side of the gully, we found the track blocked by fallen trees, so did a little bit of climbing to get over it. We really appreciated the walk and seeing this massive bridge in all its glory.
John Whitton Memorial
Sitting next to the trailhead carpark is the John Whitton Memorial. This obelisk has (or had – some are missing) plaques commemorating the viaduct’s construction. Specifically, they commemorate the designer, John Whitton and the builders who lost their lives during its construction. A short walk from the carpark, it’s worth looking at, along with th ruins of the gate-keeper’s cottage nearby.
To see what else there is to do in New South Wales, please see some of our other stories.
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