The supermarket, of course. The BBC reports:

The Linking Environment and Farming organization found 22% of 1,073 adults questioned did not know bacon and sausages originate from farms.

Some 47% of people did not know farms produced porridge's main ingredient.

I guess we have quite a ways to go in bringing awareness of food and farming into the mainstream, though this survey was surprising to me. Forget about the debate of local and organic, people don't even know food comes from farms. (Via Gristmill).