It is built to sway some twenty feet at the center of its one-mile suspension span. The secret to its durability is its flexibility that enables this sway, but that is not all. By design, every part of the bridge - its concrete roadway, its steel railings, its cross beams - is inevitably related from one welded joint to the other up through the vast cable system to two great towers and two great land anchor piers. The towers bear most of the weight, and they are deeply imbedded into the rock foundation beneath the sea. In other words, the bridge is totally preoccupied with its foundation. This is its secret! Flexibility and foundation.
That's like a family: A mom and dad, twin towers of strength providing the family with a great foundation, bending at times to keep family members together.