Château d'Aunay, Historical monument castle in Aunay-en-Bazois, France.

Château d'Aunay stands in Aunay-en-Bazois, in the Morvan, as a former medieval stronghold turned 16th-century residence. Its main building and towers were remodelled in the early 17th century, and a wing linking the square western towers was built for Charles de Mesgrigny, a grandson of Vauban. The two-storey walls are of rendered rubble stone under a long-pitched slate roof; the ribbed-vaulted kitchen survives at the eastern corner.

The site began as a medieval fortress and was transformed into a residence during the 16th century. A 17th-century renovation adapted it for Charles de Mesgrigny, a descendant of the military engineer Vauban.

The château is not open to visitors, so its cultural life is seen from outside. Each year on 17 May, bicentennial orange trees are displayed in the Grande Cour, the forecourt framed by the 17th-century orangery and service buildings. The name Aunay belonged to the Pioche family until the mid-16th century.

The château is privately owned and not open to visitors, so the interior rooms, woodwork and furnishings cannot be seen. What can be observed from outside are the remains of the drawbridge: the grooves that held its arms, the holes for the chains, and the moats around the building. The orangery and outbuildings frame the great courtyard.

Each 17 May, two-hundred-year-old orange trees are brought out and displayed in the grande cour, the forecourt framed by the 17th-century orangery and outbuildings. The château has belonged to the de Bourgoing family since 1963 and is not open to visitors, so the trees are seen from outside.