It is a typical defensive structure of a primitive type, whose appearance took shape during the 11th century.
Its main constituent elements are the high crenellated tower with a quadrangular plan, the chapel and a wall built along the natural undulation of the land which encloses a large space formerly home to residential buildings.
Of the ancient castle, located in a very scenic context, the remains of the minor Romanesque church, oriented towards the east and dedicated to San Martino, and the perimeter walls that delimit the single nave are still visible today. The decorations of the apse and the remarkable facing, made in a herringbone pattern in some points, are also admirable.
The castle of Graines can be visited freely even within the walls.
The tower cannot be visited.