Castells (castles) are human towers built in Catalonia where men, women and children alike participate. These towers may reach a height of up to ten storeys and, since 2010, are Intangible Cultural Heritage by UNESCO. Castells. Touching the sky with the hand presents us a fun and rigorous explanation of the keys to understand and enjoy these ephemeral and fantastic constructions which, besides being an expression of the Catalan cultural identity, are also a metaphor and reality of brotherly work and of the sense of continuity within the community.