Coca castle is Camelot in the musical of the same name starring Richard Harris and Vanessa Redgrave, who champions the working class by sleeping with the King’s best friend.
The friend in question is of course Lancelot, whose own castle is the even more famous Alcázar of Segovia with its mansard roofs and numerous turrets, one of Spain’s best known monuments.
You can tell Lancelot is French by the way he speaks about “the table round” and “a thing remarkable”, and by the way he lusts after our Queen, as all Frenchmen do.
The film ends with the sun rising over the Alcázar just before Arthur faces his sunset in the final battle against his greatest friend, while the Queen gets herself gone to a Nunnery.