Timeline

Heritage classified

Key figures

Origin and history

The Hourtin lighthouses, built in 1860 in the girondina commune of the same name, meet a critical need: to fill the lack of light between the point of Grave and Cape Ferret, where no lights were visible for navigators. Their original design is based on two twin towers 200 metres apart, a solution imposed by the maritime rule prohibiting two consecutive lighthouses of the same type. At the time, the Cape Ferret Lighthouse issued a fixed light, while the Cordouan Lighthouse operated by eclipses, leaving the double fire as the only viable option for Hourtin. The engineers, after rejecting the idea of wooden structures, opt for local clay bricks, which are known to be resistant to salt air, but this decision results in unforeseen costs for the bidder, forced to create his own brick factory.

The construction was completed in 1863 with the ignition of the two lanterns, initially fed with vegetable oil. The system, although functional, is costly: it requires up to five guards housed on site with their families, in three houses built simultaneously. A hippomobile tramway and a boat transport the goods and connect with Hourtin, on the other side of the lake. As early as 1894, the south tower was extinguished to reduce spending, then reassigned in the 20th century by the General Armaments Directorate (DGA) for a telemetry antenna. The North Tower underwent several technical modernizations, from mineral oil (1875) to oil steam (1904) and electricity (1955), before complete automation in 1981.

On the architectural plane, the lighthouses are distinguished by their square structure in exposed bricks, resting on a base of cut stone. The lantern, with a diameter of 3.50 meters, is decorated with volutes and surmounted by a brass and copper dome. A major innovation took place in 1894 with the installation of the first French mercury tank for a large focal unit, now replaced by a concrete platform. The ancillary buildings, including guard housing and stables, are partially left behind, although the master's house is in ruins. Ranked a historic monument in 2009, the site remains accessible via a forest road or cycle paths, offering immersion in the State forest of Hourtin, partially classified as a protection forest since 1992.

The technical history of the lighthouses illustrates the evolution of the maritime lighting systems: from first order white fixed lights in 1863 (reflective optics) to a regular flashing light every five seconds after 1894, with a current range of 21.5 miles. The national archives retain eleven plans dated from 1856 to 1862 (cote CP/F/14/17515/9), reflecting the complexity of the project. Today, the north lighthouse, which is still active, coexists with the remains of its twin, symbolizing both the ingenuity of the nineteenth century and contemporary adaptations.

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