In 1921 a few hundred dairy farmers founded Land O’Lakes in St. Paul after figuring out a way to create a longer-lasting butter. Today the farmer-owned cooperative comprises some 3,600 independent owners making 600 dairy products per year from 13 billion pounds of milk. Its offerings–including butter, cheeses, and even Purina animal feed–are sold in more than 60 countries. The farm below, in Lancaster, Pa., is home to 1,000 cows, which are milked three times a day. Their udders are automatically washed, disinfected, and dried, providing for healthier cows and higher-quality milk. When they’re done, a push of a button (by a human) allows the cows to exit the milking parlor and get back to grazing. In 2013, Land O’Lakes (No. 199 on the Fortune 500) churned out $14.7 billion in revenues.