Chevalement du Puit de la Tranchée

Reaching a height of 32 metres, the Puits de la Tranchée headframe is one of the largest of the 13 coal mine headframes preserved in France. coal mine headframes preserved in France.

Built in 1874 and 1875 by the architect Edmont Heusschen, the Puits de la Tranchée headframe is located in the coal seam of the Basse-Loire basin.

Prior to its construction, a carboniferous mining site had existed since 1541. Then, in 1743, the Lord of Montjean obtained the royal privilege of modernising coal extraction at Montjean-sur-Loire.

From an architectural point of view, the site consists of the Puits de la Tranchée, topped by a headframe, a sevenfold lime kiln, a mine and a quarry linked to the seven kilns by a railway line, the steam engine building and a port.
The Puits de la Tranchée headframe is the most powerful (32.29 metres high) of the thirteen stone headframes still standing in France.
It framed a wooden structure supporting the winch used to bring up the raw materials and descended to a height of 178.5 metres below ground to feed the seven furnaces, using a pulley system to bring the bags of coal to the surface. The kilns fired the local limestone before shipping. Production peaked in 1891 with a total of 16,206 tonnes.
Coal extraction (500,000 tonnes in total) and lime production ceased in 1892.

The entire site has been listed as a Historic Monument since 2004.