Thank you Harley for introducing and analyzing the successful urban redevelopment project in Milan. I paid visit to Porta Nuova as well during the Milan study trip. At my first sight, I thought Milan was “a grey city”, as you said, until I travelled to the massive “urban oasis”.
In terms of the public open space in Porta Nuova, which covers around 70% of the whole development area, it serves as a network in wider scale, connecting the three adjacent districts separated by transport networks. When looking into the vast public open space in detail, I was impressed by the vibrant sense of public realm. Roughly, the public open space could be divided into two themes, leisure and commercial. The leisure park is covered with plants and trees for citizens to relax, while the commercial plaza surrounded by buildings has some fountains for visitors to have fun. Within the green park, an area is assigned as children park, as shown in the feature image. Different characters are incorporated into the landscape.
What’s more, I found Milanese were invited to take part in building the park together. Citizens were given seeds and planted them with professional guidance. On the one hand, participators would realize the importance of green park; on the other hand, it would make a difference on the social cohesion through public participation.
 Hines., (2015). Porta Nuova. [pdf]. Available at <http://www.porta-nuova.com/pdf/PORTA%20NUOVA.pdf> [Accessed on 19 May 2019]
 Urbanfile., (2017). Milan | Porta Nuova – The Participating Tree Library. [online]. Available at <https://blog.urbanfile.org/2017/06/19/milano-porta-nuova-la-biblioteca-degli-alberi-partecipata/> [Accessed on 19 May 2019]