Château de Brancion, Medieval fortress in Martailly-lès-Brancion, France.

Château de Brancion is a medieval castle sitting on a rocky hilltop between Tournus and Cluny, surrounded by strong defensive walls. The structure includes several buildings and towers that show different periods of construction and military design.

A fortified site existed by the 9th century, with occupation dated 850–900 by C14 finds; Brancion is first documented in 926 in a Cluny charter. The Lords of Brancion rebuilt the castle around 1000 and added a square three-storey keep in the 12th century. Henri III Gros sold the castle and seigneurie to Duke Hugh IV of Burgundy in 1259, and it became a ducal castellany for 218 years.

The lords of Brancion carried the nickname "Gros" and the motto "au plus fort de la mêlée". Josserand III died in 1250 at the Battle of al-Mansura during the Sixth Crusade; a wall painting in the keep commemorates him and his participation. Since 2005 the association La Mémoire médiévale has managed the site and organizes cultural events there.

The site is walkable from the nearby village of Martailly-lès-Brancion and gives visitors time to explore the ruins and walls at their own pace. Parking is available in the village, with a short walk up to the castle grounds.

A wall painting in the keep commemorates Josserand III de Brancion, who died in 1250 at the Battle of al-Mansura during the Seventh Crusade. The 1964 restoration also re-inscribed the account of that battle on the keep's fireplace.