A few years ago the Lesseps Square in Barcelona was a real disaster. Streets crossing each other without any sense. Not only was it dangerous for cars, but also for people. Popularly it was known like "The nus" of Lesseps. "Nus" means knot in Catalan. 

The City Council spent a lot of money to fix it and I had the opportunity to create the campaign to launch of the new Lesseps square.

The headline of the ad says: We have undone a knot to make a square.