I’m a sucker for an aged viaduct me. I’d seen that there was something of the sort in the part of Cornwall that the wife and I make fairly regular, family-based visits to so I thought Aha! let’s go and have a look next time we’re down. Which we duly did and, well. That is some viaduct. The Treffry Viaduct crosses the thickly-wooded Luxulyan Valley, through which flows the River Par on its way to the sea at Par Sands. It’s just up the road from the biomes of the Eden Project, and not very far at all from the archetypical Cornish fishing town, Fowey, or the cliffs, beaches and tall ships of Carlyon Bay and Charlestown. It all sounds pretty idyllic when you put it like that. Yet it wasn’t always, and isn’t always thus.
200 years ago, and this part of Cornwall would have been a very different site indeed. Drive from Bodmin to St Austell now and you’ll pass the Cornish Alps, weird triangular, white mountains dotted with unnaturally blue lakes. These are the spoils of the china clay mining industry, still a major mover in this part of mid-Cornwall. Back then, the landscape would have been even more different, probably with fewer of the luxuriously-forested valleys and hills that there are today. In fact, there were mines everywhere – those that weren’t digging clay were searching for tin, iron and copper. Not for nothing is this part of Cornwall a UNESCO World Heritage site. Eden itself was a massive clay pit before its conversion, as well as playing the planet of Magrathea in The Hitchhikers’ Guide To The Galaxy in 1981 (pub quiz fact of the day). The Luxulyan Valley was at the heart of the mining area and the Cornwall Minerals Railway line that runs through it was an integral part of the distribution of its wealth.
This railway actually dates back to a tramway built in 1835 by one Joseph Austen (soon to change his name to Treffry). This originally went over this viaduct, but was re-routed when the track was upgraded to a locomotive-operated line a little later. That line is still there: you can travel on it between Par and Newquay should you wish. The original route, over the viaduct, was designed for animal haulage, and was built to supplement an earlier tramway through the valley, leading from Treffry’s massive Fowey Consols mine complex to the head of the Par Canal, at Pontsmill – also Treffry’s work, leading to the new Par docks – again, Treffry’s work. Busy man.
Treffry had previously built a leat on the western side of the valley to bring water to the mines, and this was extended across the valley on the viaduct, making it a dual-purpose structure. All in all, this is a massively impressive feat of engineering, a marvel of its age. We didn’t have the time to properly explore, but you can be sure we’ll be back – it’s explorable up to the top, over, and around, and is thoroughly lovely.