The eastern span replacement of the San Francisco–Oakland Bay Bridge was a construction project to replace an unsafe portion of the Bay Bridge with a new self-anchored suspension bridge (SAS) and a pair of viaducts. The bridge is located in the U.S. state of California, and crosses the San Francisco Bay between Yerba Buena Island and Oakland. It was built between 2002 and 2013, and does not have a name other than the unofficial name of the bridge as a whole ("San Francisco-Oakland Bay Bridge"). The eastern span replacement is the most expensive public works project in California history, with an estimated cost of $6.4 billion. Originally scheduled to open in 2007, several problems delayed the opening until September 2, 2013. With a width of , comprising 10 general purpose lanes, it is currently the world's widest bridge, according to Guinness World Records.