Four Solaire Développement

Although the city doesn't wear any emblem of the Roi-Soleil as we can find numerosous in Versailles, many centuries later, the engineer Félix Trombe will make of Mont-Louis the cradle of solar energy and will restore its name of "city of the Soleil-Roi".


Very interested in the experiments on the resistance of materials, the army allowed the installation of the first oven within the Citadel, with a solar energy laboratory.

Benefiting of more than 3 000 sunny hours, the scientists chose Mont-Louis to test works on the solar energy.

From 1949, professor Félix Trombe implants, an immense parabolic morror which will serve to concentrate the sun beams toward a only point.

The heat amounts to more than 3 000°C, a never reached temperature, long lasting and free of charge. That's the first solar furnace at double reflection over the world.


After several years, the solar furnace has been abandoned for bigger structures (Odeillo). 

The oven is sold to the municipality of Mont-Louis. And it has been moved to a bastion of the city to make it visited.


Since 1993, according to the framework of the regional program Hélio-Parc, the Four Solaire Développement SARL runs the solar furnace in partnership with the CNRS (National center for scientific reseach) for the scientific research aspect.


Faithful to the Mont-Louis pioneer's tradition, this society is the very first one to use a solar furnace for industrial and craftmade productions: art ceramic cooking, bronze or aluminum fusion to manufacture usual or original objects as the whistle of the famous Yellow train

Four Solaire Développement

Résidence Vauban

66210 Mont-Louis

Tél. : +33 (0)4 68 04 14 89

Fax : +33 (0)4 68 04 26 60

At the occasion of a fascinating visit, the guides will reveal you their technique secrets and will lead you to the heart of the installations. You will discover at the shop thier productions of art ceramic and bronze realized there.


From november 2016 to april 2017

Guided visit hours


From may to october

10h30 - 11h30 - 14h - 15h - 16h - 17hevery day

18h from june 15th to september 15th