Tarn (river)

The Tarn (Occitan: Tarn, Latin: Tarnis, possibly meaning 'rapid' or 'walled in') is a 381-kilometre (237 mi) long river in southernFrance (régions Languedoc-Roussillon and Midi-Pyrénées), right tributary of the Garonne.

The Tarn runs in a roughly westerly direction, from its source at an elevation of 1,550 m (5,085 ft) on Mont Lozère in the Cévennesmountains (part of the Massif Central), through the deep gorges and canyons of the Gorges du Tarn (that cuts through the Causse du Larzac), to Moissac in Tarn-et-Garonne, where it joins the Garonne 4 km (2.5 mi) downstream from the centre of town.

Its basin covers approximately 12,000 square kilometres (4,600 sq mi), and it has a mean flow of approximately 140 cubic metres per second (4,900 cu ft/s).

The Millau Viaduct spans the valley of the River Tarn near Millau, and is now one of the area's most popular attractions.

Navigation

Tarn gorge, seen from the point sublime

The Tarn was once navigable from its junction with the Garonne to Corbarieu, near Montauban. This stretch of river included seven river locks over a distance of 38 kilometres (24 mi). The canal was linked to the Canal de Garonne in Moissac by a branch lock upstream of the first river lock, and again, via the Canal de Montech, at Montauban.

The two access points from the Canal de Garonne have both been restored, and boats can again access the immediate reaches of the river at these points. Additionally the first river lock, between Moissac and the Garonne itself, has been flooded by the barrage for the Golfech power station on the Garonne, and is permanently open to boats which can thus reach the Garonne and navigate a short distance of that river.

The remaining six river locks are disused and unnavigable. A proposal exists to restore the five river locks between Moissac and Montauban, thus creating a waterway ring consisting of the Tarn from Moissac to Montauban, the Canal de Montech to Montech and the Canal de Garonne back to Moissac.