Hidden Clermont-Ferrand: The Oil Pit of Poix

One region where earth oil is very common is in the volcanic district of Clermont-Ferrand, France; it is not only found in combination with the general mass, but in an actual spring, the Fontaine de Poix.

– Ludwig Meyn

It’s a little-known fact that Auvergne — like the “Wild West” American states so scoured by oil prospectors in the twentieth century — also has its own deposits of “black gold”. This oil, which is said to have been known to the ancient Romans, is located not in the wayward, lofty heights of the Sancy Mountains, but in the vicinity of Clermont-Ferrand.

Situated on the puy de la Poix, a volcanic hill between Aulnat airport and the puy de Crouël, the oil pit of Poix is one of Auvergne’s natural wonders, a marshy pond composed of bitumen, salt water, and other hydrocarbons. In the nineteenth century, at least one company — according to the British engineer Thomas Boverton Redwood — attempted to set up a serious drilling project. Eventually, however, all works were abandoned due to lack of funding. Here’s an excerpt from Redwood’s Petroleum: a Treatise on its Geographical Distribution (1896):

“The Tramway Company at Clermont-Ferrand sank a water-well to a depth of 165 metres, and found salt water, with which were associated drops of petroleum. At puy de la Poix, a well was sunk to a depth of 50 metres, at Malintret to 42 metres, and at Cœur to 60 metres, but the work was abandoned for want of funds. A sample of oil, which was associated with salt water smelling of sulphuretted hydrogen, was taken by M. Juncker at puy de la Poix. The “bitumen” yielded 52 per cent of ‘crude oil’. Distillation commenced at 125° C., and was carried to 200° C.”

Today the oil pit of Poix — a true testament to Auvergne’s remarkable geological heritage — is a freely accessible nature reserve. Even so, it remains one of the most interesting corners of “Hidden Clermont-Ferrand”, an attraction that continues to elude all but the most lynx-eyed travellers.