Bosco Verticale (Vertical Forest) is a project for metropolitan reforestation that contributes to the regeneration of the environment and urban biodiversity without the implication of expanding the city upon the territory. Bosco Verticale is a model of vertical densification of nature within the city. It is a model that operates correlated to the policies for reforestation and naturalization of the large urban and metropolitan borders (Metrosbosco). Metrobosco and Bosco Verticale are devices for the environmental survival of contemporary European cities. Together they create two modes of building links between nature and city within the territory and within the cities of contemporary Europe.