On March 30, 2015, Facebook officially opened its new campus in Menlo Park in Silicon Valley, though employees started moving in over the weekend. Designed by starchitect Frank Gehry, the 430,000-square-foot complex has the largest open floor plan in the world and already received its LEED gold certification from the U.S. Green Building Council. The building itself is "a cavernous office space on stilts, sandwiched between parking below and a roof garden above," and that roof garden spans nine acres and includes a half-mile walking loop and more than 400 trees. In a written statement, Frank Gehry said "From the start, Mark [Zuckerberg] wanted a space that was unassuming, matter-of-fact and cost effective. He did not want it overly designed. It also had to be flexible to respond to the ever-changing nature of his business — one that facilitated collaboration and one that did not impose itself on their open and transparent culture. This is the building that we created for him."