Timeline

Heritage classified

Key figures

Origin and history

The Cammazes tunnel, also known as the Vauban vault, is a 122-metre long and 3-metre-wide hydraulic structure built between 1686 and 1688 under the direction of Vauban. It allows the Black Mountain channel to reach the Saint-Ferréol reservoir, thus feeding the Canal du Midi. This project, originally envisaged by Pierre-Paul Riquet (died 1680), was taken over by Vauban in a memorandum dated 5 March 1686 to solve the water supply problems of the canal, then in poor condition and threatened with abandonment.

In December 1685 Vauban inspected the Canal du Midi and proposed a rescue plan including major hydraulic works. The Cammaze tunnel, entrusted to Antoine Niquet, commissioner of fortifications, is dug by hundreds of workers. An accident in April 1687 caused six deaths and three injuries. The vault, completed in two years, was originally decorated with symmetrical carved facades dedicated to Louis XIV, one of which was destroyed during the Revolution.

Ranked a UNESCO World Heritage Site in 1996 and listed as a Historic Monument in 1997, the tunnel illustrates 17th century engineering. In 1846, its top was wooded to fit into the landscape, and a guard house was built in 1847. Today, despite its historical importance, it is crossed by departmental 629 without always attracting attention, and suffers from degradations related to channel management.

The Cammazes tunnel remains a key testimony to the hydraulic engineering of Vauban and the construction of the Canal du Midi, a colossal project of the reign of Louis XIV. Its role in supplying water to the Saint-Ferréol reservoir was crucial for the sustainability of this waterway, still in service today. The original facades, partially preserved, recall its royal status, designed to glorify the monarch while serving an essential practical function.

External links