Between Capestang and Colombiers, Pierre Paul Riquet gives up on the tracing advocated by the Knight of Clerville, which has to cross the river Aude. Instead he prefers to cut into the sandy tuff of Enserune hill, subject to landslides and pemeable to water. His detractors had finally a good reason to let him down and Colbert, following Louis XIV orders, asked Pierre Paul Riquet to suspend work . He pretended to obey and sent labourers to work on another section of the Canal.
With candle lights Pierre-Paul Riquet took them through the 165 metres of vaulted tunnel, 8 metres high and as many wide. Dumbfounded they had to realize that the Canal went through !
This tunnel was very much ahead of its time and it is only in the XIX century that this kind of works became commonly uesd with the building of the Railroads.
