Oppidum d'Ensérune

The Malpas tunnel carries the Canal du Midi under the d'Ensérune hill in Hérault, France. Excavated in 1679, it was Europe's first navigable canal tunnel and is a monument to the determination of Pierre-Paul Riquet, the chief engineer. It is located in the commune of Nissan-lez-Ensérune near to the archaeological site Oppidum d'Ensérune. There was great disappointment when the works reached the hill d'Ensérune. A few metres of digging in hard rock revealed a very brittle sandstone subject to slippage. Colbert, the prime minister, halted the works when he was made aware of the situation. The portal was blocked and the workings re-sited. Riquet's detractors took advantage of this situation to impede the project. Colbert announced that he would send royal commissioners to decide the canal's future. The advice of the Chevalier de Clerville, architect to Louis XIV, was to cross the river Aude rather than tunnel through the hill. Riquet, however, maintained his preference for a tunnel because of the extra problems that crossing the Aude would create. Riquet's response was to ask his master mason, Pascal de Nissan, to continue tunneling in secret despite the risk of collapse. In less than eight days, the tunnel was complete with a concrete ceiling throughout. The tunnel is 165m long with an arch 8m above the canal's surface, and removed the necessity for an extra lock. By the time the Malpas Tunnel was excavated in the seventeenth century, the hill had already for several centuries been the site of a tunnel, dug in the Middle Ages, to drain the Étang de Montady. This pre-existing tunnel is said to have been Riquet's inspiration for the Malpas Tunnel. In the nineteenth century, a third tunnel was excavated, passing through the Hill d'Ensérune beneath the Malpas tunnel to house the Béziers to Narbonne railway line.

The Étang de Montady (English: "pond of Montady") is a drained endoreic pond or lagoon, is now more accurately a former freshwater wetland, located near Montady and Colombiers, midway between Béziers and Narbonne in the western department of Hérault in southern France.

Montady (French pronunciation: [mɔ̃tadi]; Occitan: Montadin) is a commune in the Hérault department in the Occitanie region in southern France.

Nissan-lez-Enserune (French pronunciation: [nisɑ̃ lez‿ɑ̃seʁyn]; Occitan: Nissa d'Ausseruna, Niça d'Ausseruna), also spelled Nissan-lez-Ensérune, is a French commune in the department of Hérault, region of Occitania, situated just south of Béziers. Its inhabitants are called Nissanais in French.

Colombiers (French pronunciation: [kɔlɔ̃bje] ; Occitan: Colombièrs) is a commune in the Hérault department in southern France.

Poilhes (/pɔj/) is a commune in the Hérault department in the Occitanie region in southern France.

Maureilhan (French pronunciation: [moʁɛjɑ̃]; Occitan: Maurelhan) is a commune in the Hérault department in southern France.

Lespignan (French pronunciation: [lɛspiɲɑ̃]; Occitan: Lespinhan) is a commune in the Hérault département in the Occitanie region in southern France. Experiencing a Mediterranean climate, it is drained by the Aude River and various other small streams. The commune boasts a remarkable natural heritage: three Natura 2000 sites (the "Lower Plain of the Aude," the "Lower Course of the Aude," and the "Hills of Narbonnais"), two protected areas (the "Lower Plain of the Aude and Collines d'Enserune" and the "Lower Plain of the Aude"), and eight natural areas of ecological, faunal, and floristic interest. Lespignan is a rural commune with 3,355 inhabitants in 2022, having experienced a significant population increase since 1962. It is located within the Lespignan urban area and is part of the Béziers catchment area. Its inhabitants are called Lespignanais or Lespignanaises.

Maraussan (French pronunciation: [maʁosɑ̃]; Occitan: Marauçan) is a commune in the Hérault department in southern France. It lies approximately 8 km northwest of Béziers, on route D14 ( Av de Béziers ), a busy route for commuters to Béziers. Chateau Perdiguier lies just outside the town on the cross road D39 (Route de Tarbaka) leading down to the river Orb.

Salles-d'Aude (French pronunciation: [sal dod] ; Occitan: Salas d'Aude) is a commune in the Aude department in southern France.

The Capestang bridge over the Canal du Midi at PK 189 at Capestang is a very important structure for those wishing to motor on the canal. It is used as a measuring device as it is the lowest structure on the canal. A boat, with an air draft under 3.3 m (11 ft) at the center and assuming a beam no more than 5 m (16 ft), a height of no more than 2.4 m (7.9 ft) at the extremities, should make it under the bridge. A British boat builder who builds boats for several of the boat hire companies in France builds their boats to meet these requirements. Even though rebuilt in recent times, being historic, it was felt necessary to retain its small dimensions.

Capestang (French pronunciation: [kapɛstɑ̃]; Occitan: Cabestanh) is a commune in the Hérault department in southern France.