German industrialization was marked by a shift from small-scale to large-scale production. By the beginning of the twentieth century, many industrial workplaces had reached monumental proportions. Men, women, and older children worked in these factories, putting in ten- to twelve-hour days. The image below shows the sprawling Opel factory, which manufactured machinery and started producing automobiles in 1899. The Opel factory still makes automobiles in Rüsselsheim today.