In 1679, Pierre-Paul Riquet continued the construction of the Canal du Midi, but came up against a real difficulty.
When the construction site of the Canal du Midi reached the Ensérune hill, under a few meters of very hard ground, hides a very friable sandstone mountain, prone to landslides. Minister Colbert, who was quickly alerted to the situation, had the work interrupted.
Riquet's detractors seem to have succeeded, the gallery has just been blocked and the site moved. The entire project was thus threatened and Colbert announced the visit of the royal commissioners to decide on the future of the Canal. Pierre-Paul Riquet was then on the verge of losing his bet: he had preferred to pierce this hill rather than follow the advice of the Chevalier de Clerville, Louis XIV's architect, who proposed to cross the Aude.
Pierre-Paul Riquet then asked the Nissan master-mason Pascal to continue the work in secret, despite the risk of collapse. In less than eight days, a test tunnel is pierced, supported by a vault cemented from end to end.
It is the first tunnel-channel ever built.
173 metres long, 6 metres wide and 8.5 metres high, with 30 arches supporting the vault, the tunnel earned its name, "Malpas" meaning "bad passage", but it actually owes its name to the Malpas Pass under which it was bored.
And in Toulouse...
And since 2020 the Canal du Midi disappears on a hundred meters in Toulouse, in front of the Matabiau station.
These are not the planks of Deauville, these are the planks of Toulouse.
Translated with www.DeepL.com/Translator
(free version)