The Bosco Verticale towers, a skyscraper composed of planted balconies that reach into Milan’s sky, earned the 2014 International Highrise Award given by the Frankfurt Museum of Architecture. The biannual award recognizes the most beautiful and innovative new structures over 100 meters tall. The forested towers were cited as a powerful example of the symbiosis possible between architecture and nature—representative of a great possibility for new developments in high-density areas. “It is a radical and daring idea for the cities of tomorrow,” said Christoph Inegenhoven, president of the award’s jury.

Boeri Studios created the residences for the redeveloped Porta Nuova district of Milan, using advanced technologies to obtain high levels of sustainability, as well as manual techniques that allowed the installation of over 800 trees and 2,000 shrubs (plus the addition of over 1,200 insects to maintain a balanced ecosystem).

The prize, for which over 800 high-rises were evaluated for future-oriented design, functionality, innovative building technology, and sustainability, is considered the most prestigious award given for skyscrapers. The Bosco Verticale—which means Vertical Forest—brings 3.5 acres of vegetation to the skyline of Milan, a city of few green spaces and some of the most polluted air in Europe. The plant life filters dust particles, absorbs carbon dioxide, and protects the building from radiation.

As populations skyrocket and rapid urbanization stresses the housing and food supply, radical and sustainable solutions to density will inevitably be at the forefront of new ideas in architecture. The Vertical Forest is emblematic of a growing architectural movement toward the greening of buildings, which includes using building surfaces for urban farming as well as Boeri’s method of creating parkland in unlikey places. The award highlights an exciting change in the way we might conceive of the skyline of the future, where nature’s leafy profusions will overtake the straight lines of human constructions.