The construction of Alcoutim’s Castle began during the rule of Dom Dinis, in the fourteenth century, in order to defend the border and control the trade on the river Guadiana.
In the sixteenth century, the pointed arch gate on the side facing the river was erected and several edifications adjoining the North Wall were built. In the second half of the seventeenth century and eighteenth century, military engineers built a platform on this castle to hold a gun battery of seven canons aimed at the town of Sanlucar de Guadiana.
In 1992/1993, the Municipality of Alcoutim developed a project to rehabilitate the Castle, which resulted in the find of a few archaeological remains. These remains were researched and duly regarded with the creation of the Museological Exhibition on Archaeology in 2000. In 2005, the gunpowder magazine held the exhibition Timeless Games – Exhibition of Trays and Game Pieces from the Old Castle of Alcoutim.