Haulingsystemiskeyequipment in the maincableerectionof suspension bridge. It is acomplex system which consistofmany kinds of mechanicand the operators.
First introduced in the late 1800s to save the strain on horses hauling carts up the city's steep inclines, the 15, 500-pound cable-powered cars grip a continuously moving underground cable with pliers-like gear to travel the streets of San Francisco.