Final answer:
In Act 1 of Romeo and Juliet, according to the Prince, the Capulets and the Montagues have disturbed the peace of Verona's streets three times.
Step-by-step explanation:
In Act 1 of Shakespeare's play Romeo and Juliet, the Prince states that the Capulets and the Montagues have disturbed the peace of Verona's streets three times. This is mentioned in the Prince's speech after the brawl between the two families' servants. The Prince warns the Capulets and the Montagues that any further disturbance will be punishable by death. The repeated clashes and violence between the two feuding families set the stage for the tragic events that unfold throughout the play.