Vallon-en-Sully is a commune in the Allier department in Auvergne-Rhône-Alpes in central France.

It is home to a host of beautiful châteaux (i.e. castles), with the most notable being Le Creux.

The Château is a building with classical and symmetrical architecture, composed of a central main building, raised on a ground floor and two floors, surmounted by a high French-style attic, confined by two wings, projecting on the courtyard side and set back on the park side, each surmounted by an independent high roof.

On each of the two facades, the three central bays form a slightly projecting avant-corps, surmounted by a triangular pediment.

The arrival facade is preceded by a forecourt lined with outbuildings and a courtyard; the latter is confined at each of its four corners by a pavilion with a mansard roof.

On the side is the vegetable garden and behind, an English park.

The seigniory of Creux belonged in the Middle Ages to the family of La Faye. In 1519, Jeanne de La Faye married Gilbert de Fougières, who, in 1546, bought the seigneury of Creux from her brother-in-law. Le Creux then entered the de Fougières family, whose descendants have kept it ever since.

In the 1770s, the Château du Creux, its outbuildings and its surroundings were redesigned by the Parisian architect Nicolas-Martial Foacier, at the request of François Marie, count of Fougières, marshal of the camps and armies of the king, deputy governor of the Dauphin and children of France, Lieutenant General of Bourbonnais (1721-1787). His son, Louis Joseph de Fougières (1773-1841), left an only daughter, Adélaïde Hyacinthe de Fougières (1819-1891), whose marriage in 1837 to Christian de Nicolaï brought Le Creux into the house of Nicolaï.

Between 1883 and 1889, she had her Château du Creux restored by the Amiens architect Edmond Duthoit. In March 1951, the roof of the castle was partially damaged by a fire, then restored identically in the following months.

The building is registered and partially classified by the respective decrees of March 5, 1992 and March 10, 1995 as historical monuments.