CURIOSITIES:QUESTION: How do you build a relatively lightweight stone bridge across a deep and narrow gorge? Answer: With a pair of spectacles.
At least, that's what John Hill did in the early 1870s when, as the engineer for Co Clare, he was faced with the problem of how to bridge the Aille River gorge when designing the Lisdoonvarna-Ennistymon road.
If you're feeling intrepid, and share my love of bridges, then it's worth looking out for this intriguing construction next time you are in the area.
It's a couple of kilometres from Lisdoonvarna on the N67, except you'll need to be sharp-eyed: you won't notice anything special from the road, and there is no signpost (at least, not the last time we were there). But a stile and a path lead down to the river, from where you can admire the "spectacles".
John Hill's problem was that the gorge is relatively deep - up to 25 metres below the road level in places - and a solid stone bridge would be massively heavy and difficult to support. His solution? Remove most of the bridge's filling and weight, by running a large tunnel through the centre and creating a lighter structure.
As one contemporary account has it: ". . . the architect, perhaps, with a view to make the structure as light and graceful-looking as possible, contrived a circular opening where the dead work should be, and now there are two apertures - one below, through which the water flows, and the circular one above, which is rather a novel feature in bridge-making."
Seen from the river below, the result looks like a pair of spectacles, yet from the road above it looks like any other bridge - you'd never know it was unique in Ireland.
Naturally, those in the know have been shouting about it for some time. It featured in Michael Barry's 1985 book, Across Deep Waters: Bridges of Ireland, and in a couple of books by engineering historian Dr Ron Cox, which is where I first came across it.
Google images will bring you several images, including a delightful Victorian coloured postcard, depicting a party on the bridge.
Happily, Hill's lovely bridge is now also mentioned in a lot of the local tourist information. Nice to see some engineering heritage finally making it on to the tourist map.
Mary Mulvihill