'Forest in the sky' under construction in Milan
Construction on an Italian block of flats known as the world's first "forest in the sky" has started.
The Bosco Verticale buildings - which stands for "vertical forest" - are set to feature 730 trees, 5,000 shrubs and 11,000 ground plants, on its 27 floors.
A team of horticulturalists has been enlisted to tend to the trees, which will grow to heights of up to 30ft.
The structure - which will be based in Milan - is designed by architect Stefano Boeri and will include wind, solar and recycling systems.
