When you drive south from Swansea on Tasmania’s east coast you pass an interesting old convict construction called Spiky Bridge. It’s about 7kms south of Swansea on the Western side of the road and there is plenty of room to pull in for a closer view.
History has it that the bridge was constructed by convicts stationed at the Rocky Hills Probation Station and until the road and bridge was constructed it was a perilous journey from Swansea to Little Swanport, near Triabunna. The story goes that a particularly bumpy ride home after a night out prompted the Superintendent of the Probation Station, Major de Gillern to commence the roadworks and construction of the bridge.
The bridge was built of stones gathered locally and was a dry stone wall construction. (no mortar or cement used). Blogger, On the Convict Trail, explains the groove in the wall –
Also of interest is the interesting engineering design built into the bridge for the removal of water from the bridge roadway. Clearly visible on the outer face of the bridge is the water channel running down to the arch beneath the bridge, leading down from a slot at the base of the roadway wall. A very simple method for the times to keep excess water away from the roadway surface.
Why did they make it so spiky? Well, no-one really knows the answer to that question. One theory is to stop cows falling off the bridge into the gully below but the more popular theory is the convicts did it out of spite to exact revenge on their supervisor, or just because they could! I rather like the second theory, don’t you?