The Oakland Bay Bridge in San Francisco boasts more superlatives than any bridge on earth. Bridge builders of the depression era defied logic and economics and succeeded in building an 8 mile long structure connecting Oakland and San Francisco. Engineer Charles Purcell built two suspension bridges side by side on the San Francisco side of the bay, then built the largest bore tunnel in the world to connect the west side with Oakland's eastern shores. A cantilever bridge and a truss section connect the tunnel with the eastern shore. Twenty-two men plunged to their death building the bridge, as diver bill reed risked his life helping to position the giant concrete foundations far below the waterline. Once completed, the San Francisco Oakland Bay Bridge soon became the busiest bridge on earth, carrying more than 280,000 cars every day.