The spatial organization of a fair is a monotone, dreary affair; for a celebration like Juvenalia (a youth fair in Madrid), then, it can be a problem. We tried to intensify its basic features: displays and attractions are concentrated as much as possible, while at the access we leave a large eventless space. To the mandatory streets, a diagonal is added. Contrast between crammed and labyrinthine space and another one that is free and open. Spatial organization as entertainment: combined with a location system, the entire fair becomes the site of a game of hide and seek. The façade of the exhibitors and attractions overlooking the open space is full of projections, the biggest one being the location panel of the hide and seek game.