Integrating as much greenery as possible in the heart of urban spaces: it has become a priority for some of the world's biggest cities which are now confronted with excessive urbanisation. In Turin, in northern Italy, where it took 5 years to build the imposing "25 Verde", a residential building comprising of 63 apartments mixing architecture and nature. Creating a green oasis in the middle of the city... Luciano Pia, the architect who worked on the project, successfully met this incredible challenge.