By JOYCE KHOO

If you’re visiting San Francisco in a week’s time, pencil in a date with the newly re-imagined California Academy of Sciences. Designed by Pritzker Prize winner Renzo Piano, the 410,000 sq ft compound took three years to build, at a cost of US$500 million.

Sitting squarely in the middle of the city’s Golden Gate Park, the new facility combines all twelve buildings of the Academy of yore under one 2.5 acre-large green roof. The building is a veritable tribute to the principles of sustainable development, with 60,000 photo-voltaic cells covering a glass canopy that frames the building.

Crowned, literally by a “living” roof  - a 2.5 acre expanse of native Californian plants and wildflowers - it also houses a NASA-sponsored planetarium, 38,000 live animals, an aquarium, a natural history museum, and San Francisco’s first rainforest. The California Academy of Sciences opens officially on 27 September.