Authorization for the Tournon-Tain bridge was obtained at the end of 1823.

The bridge was to be built at the ‘contractors’ own risk’, in only 18 months, which was extremely rapid given the technical means of the time.

The work begins in the spring, and they experienced the hazards of a very new construction site as well as those of a river with violent and devastating floods.

The high waters of November 1824 stopped the construction site for many weeks and, ultimately, destroyed a large part of the pile works where the pouring of hydraulic concrete had begun.

They had to start again!

The Seguin brothers courageously resumed work on December 15.

A certain number of documents have been preserved in the company’s archives, giving an idea of the work carried out and the conditions of such a site.