Château de Montois, château in Ressons-le-Long, Aisne, France

Château de Montois is a castle in Ressons-le-Long located where the valleys of the Aisne and Retz meet. It began with a pavilion in 1736 and received two side pavilion additions with local-style gables between 1875 and 1890, along with two octagonal towers dating from the 16th century.

The central pavilion was built in 1736. Between 1875 and 1890 two side pavilions with stepped gables and two octagonal turrets were added. Émile Gaillard traced the estate's origins and owners in his 1905 monograph on Ressons-le-Long. The whole domain, including vestibule, staircase, cellars, terrace, portal, chapel and water features, was inscribed as a monument historique on 9 April 2024.

The name Montois refers to the hamlet where the castle stands. Visitors see a building that shows different phases of use: from rural farmstead to aristocratic residence, with each layer visible in the architecture.

The estate lies in the hamlet of Montois, in Ressons-le-Long, where the Aisne and Retz valleys meet. The garden is listed in the pre-inventory of remarkable gardens, and its park was reworked in the 1920s by landscape gardener Édouard Redont. The whole domain, including the chapel, fountain, basins and terrace, was inscribed as a monument historique in April 2024.

The grounds were reworked in the 1920s by Édouard Redont, the landscape architect behind Reims's Parc de la Patte-d'Oie and its horticultural garden. The garden is listed in the pre-inventory of remarkable gardens, and the whole estate, from gate to chapel, was inscribed as a monument historique in April 2024.