On September 18, 1468, a humiliated King Enrique IV of Castile met his sister Isabella at Toros de Guisando, a kind of Iberian Stonehenge. The bulls or pigs, of Celtic origin, carved from granite around 300 BC, were the silent witnesses to the embrace between brother and sister and to the signing of the Treaty of Guisando. Through this treaty, Enrique repudiated his own daughter, Juana, and designated Isabella as heir, with a further condition that the princess should get the approval from the king to her husband. This was the last stage of the struggle between the great Castilian families to control weak and manageable King Enrique. His daughter became known as Juana la Beltraneja, as it was said that her father was Beltrán de la Cueva, the favourite…