Arno and Elise need to escape this area. To this end, they rush and find a balloon. Elise quickly climbs in and asks Arno to cut the balloon free while she covers him. Throughout this part, try to keep the fighting to a minimum. It is very easy to get overwhelmed but good parry work can stop the worst from happening.
Immediately in front of you is the first rope. Just run over to it and interact with it. This will have Arno slice through it.
Head over to the Southeastern side. This is the second rope you should be slicing through.
Go to the Southern portion of the courtyard. This is the final rope. Cut it and events will move forward.