Built during the 13th century, the Château de Montgilbert is located at the top of a rocky hillock in one of the turns of the Vareille, a brook feeding Sichon, a small tributary of the Allier River. It is composed of two concentric walls. The external fortification, adapted for ground combat, reinforces the defences (towers, arrow slits) in the gently sloped west and south sides, and delimits a low courtyard that contained the servants' quarters. This enclosure was expanded during the 15th century with artillery batteries and a bastion with thick walls that covered the overexposed original entry.