The Canal des Ardennes is 87.779 km long and has 44 locks with a tunnel in Saint-Aignan. As originally built it was 5.5 km longer, entering the Aisne further downstream, but this section was bypassed by the Canal latéral à l'Aisne in 1841. The canal connects the village of Pont-à-Bar to the junction with the lateral canal downstream of Vieux-lès-Asfeld. The first part of the canal is 39 km long and crosses the threshold between the valleys of the Meuse and the Aisne by following the Bar Valley, with a short cut through a tunnel at Saint-Aignan. This section of the canal up to the summit level is supplied with water from the Lac de Bairon, with water pumped from the Meuse. After the summit is reached the canal quickly drops down to the Aisne through a series of 27 locks in just 9 km. From Semuy the canal closely follows the course of the Aisne. In places it even follows the old winding river bed, but mostly runs straight through new cuts. On the Aisne side the canal is fed directly by the river Aisne through diversion weirs at Vouziers, Rilly, Givry, Biermes, and Asfeld. On the Aisne side the Vouziers Branch, 12.066 kilometres long, rises 9 m through 4 locks to the town of Vouziers. The canal has two separate sections and two series of locks, as if it were made up of two distinct canals. The first is the portion from the Meuse to the Aisne river at the junction with the Vouziers Branch. The second is the entire length parallel to the Aisne beginning at Vouziers and continuing parallel to the Aisne to Vieux-lès-Asfeld.
Altitude at Vieux-lès-Asfeld: 60.55 metres.
Altitude at Pont-à-Bar: 151.30 metres.
Altitude at the summit level: 165 metres.
Average lock height: 2.68 metres.
*Aisne side: 2.70 metres.
*Meuse side: 2.57 metres.
History
The first canal projects in the region date from 1684 under the Louvois ministry and consisted of using and extending the course of the Bar which was then navigable. Various proposals were made over the decades and, in letters patent of June 1776 – almost a century later – the Prince of Conti was granted the privilege of its construction and operation. The prince died shortly after and nothing was done. After the French Revolution of 1789 the National Constituent Assembly relaunched the project but found fault with previous studies and the project did not proceed. In "Year VIII", the local general councilors reminded the government of the project. The prefect Joseph Frain supported and argues for the canal, on the basis of a new route, in a report on 4 October 1800 to the Interior Minister, Lucien Bonaparte. The subsequent Interior Minister, the scientist Jean-Antoine Chaptal, agreed to undertake construction but granted only very limited funds. Work began slowly It became more important during the Bourbon Restoration with the launch in 1820 of a loan to finance the project. The opening of the canal took place between 1827 and 1835 with modernization between 1842 and 1846. The Vouziers Branch was opened to shipping in 1836. For the part parallel to the Aisner downstream of Lock No. 26 at Rilly initially, until the dams were built, these parts of the navigable canal were connected by a series of artificial reaches. From 1842 to 1845 improvements were being made, in particular through the creation of the reservoir and the artificial Lake Bairon.
Appearance of a Weed
The plant Matricaria discoidea, a native of North America, appeared in 1861 along the Canal des Ardennes and then from 1880 to 1895 in the North of France. It spread so rapidly that it displaced the native Tripleurospermum inodorum "to seem as native as he".