Facebook has revealed images of a new building completed at its Menlo Park headquarters in California. Titled ‘MPK 21′, the structure — as with the campus’ other buildings — has been designed by Frank Gehry and was constructed in less than 18 months. The offices are topped with a 3.6-acre roof garden that features over 200 trees and a half-mile meandering pathway. The company also wanted to establish a closer relationship with nature inside the building: The ‘town square’ is a sheltered green space with 40-foot-tall redwood trees, while ‘the bowl’ has been conceived as amphitheater-style courtyard.