The iron and copper ore regions of northern Michigan and Minnesota were easily accessible by ship. At the confluence of east and midwest, Detroit's central location gave its auto producers easy access to the capital and markets necessary for its phenomenal growth.

Detroit's first auto plants were small operations, but as Ford pioneered the techniques of mass production at the new Highland Park Plant, with its cuttingedge assembly line techniques, the scope and scale of auto production grew accordingly. By the 1920s, Dodge had built the enormous Main Plant in Hamtramck, just a short distance from Ford's pioneering Highland Park facility. But by far the most ambitious and landscapealtering plant was Ford's vast River Rouge complex. Finished in 1927, the River Rouge plant consisted of nineteen separate buildings in a vast industrial complex that sprawled over more than two square miles. The River Rouge plant was a wholly selfcontained center of production. It included a manmade deep sea harbor, the world's largest steel foundry, ninetyfour miles of railroad track, and stamping, glass making, and auto assembly buildings, among many others. At its peak, over 90,000 workers toiled at the Rouge. The looming plant became an international phenomenon, visited and photographed by thousands of international visitors, the subject of film reels celebrating American industrial might, and an important model for the industrialization of the Soviet Union.