Warwick, with the captive King Henry in his train, meanwhile moved to block Queen Margaret's army's route to London. He took up position north of St Albans astride the main road from the north (the ancient Roman road known as Watling Street), where he set up several fixed defences, including cannon and obstacles such as caltrops and pavises studded with spikes. The Yorkists were defeated in this battle that saw Henry VI returned to Lancastrian hands. Although Margaret and her army could now march unopposed on to London, they did not do so. The Lancastrian army's reputation for pillage caused the Londoners to bar the gates. This in turn caused Margaret to hesitate, as did the news of Edward of March's victory at Mortimer's Cross. Instead of marching on London to secure the tower after her victory, Queen Margaret hesitates, and thus wastes an opportunity to regain power. Edward of March and Warwick entered London on 2 March, and Edward was quickly proclaimed King Edward IV of England.