[alex4nder]

You mean River Rouge. It was an amazing plant.

[wglb]

You are correct: http://en.wikipedia.org/wiki/Ford_River_Rouge_Complex. It is on the Rouge River, which is what was in my memory.

I had a chance to visit it before they stopped the tours. The most impressive part was the plant where they took in a huge chunk of steel and heated it red hot, then repeatedly rolled it until it was thin, then rolled it up.