Back of card: Bridging San Francisco Bay Metropolitan Area. This bridge is a double deck structure eight and one quarter miles long. The upper deck is 58 feet wide divided into six auto lanes. The lower deck will carry three auto truck lanes and two interurban car tracks. The entire project cost $79,500,000, the bridge proper $57,500,000. Main suspension spans are 2320 feet in length with a vertical clearance of 185 feet.