Construction began last week on the 拢3m Xstrata Treetop Walkway in Kew Gardens, west London, designed by Marks Barfield Architects.

Commissioned to celebrate the gardens鈥 Festival of Trees, the 18m high structure will be built by Britland, with structural and environmental engineering by Jane Wernick Associates and Atelier Ten. It will open to the public in May 2008.