During the last 100 years, General Motors’ assembly lines have mass-produced millions of cars and trucks, in addition to tanks, tractors, locomotives, refrigerators, radios and other products. Since 1931, GM has been the largest automaker in the world, with plants scattered across six different continents.

Below is a slideshow that illustrates how GM’s plants and production processes have changed over the decades. Photos courtesy GM Media Archive and Sloan Museum.