Krakow will install its first “CityTree,” a large-scale moss wall designed to be an urban air purifier, later this year, reports LoveKrakow. The “CityTree” design by German bio-tech company Green City Solutions was the winner of Smogathon 2016, a competition held in Krakow supporting the development of hi-tech solutions aimed at combatting air pollution. The 4m tall, 3m wide and 1m thick design includes genetically engineered moss, a watering system, and data collecting smog sensors. The price tag is approximately 25,000 euros. Green City Solutions claim the “CityTree” produces air filtration equivalent to 275 urban trees. The moss wall will be installed in one of three locations: ICE Congress Centre, Kino Kijow or Rondo Mogilskie. Although the installation of only a single unit makes this more of a symbolic gesture, it is none-the-less the introduction of an innovative new tool in the fight against smog.