Treaty of the Bulls of Guisando

The Treaty of the Bulls of Guisando (Spanish: Tratado de los Toros de Guisando) is the name of a treaty agreed on top of the hill of Guisando near the Bulls of Guisando (located in Ávila, Spain) on 19 September 1468, between Henry IV of Castile and his half-sister Isabella of Castile. The treaty granted Isabella the title of Princess of Asturias and so she became heiress presumptive to the Crown of Castile.