The Sunnyside Diner is a small diner in the middle of nowhere somewhere in the United States.
History[]
While driving through the area, the Winchesters stop at the diner where Dean orders Sam to get him an onion burger and pie. Moments after Sam enters the diner, the Impala's radio flickers and goes out and Dean enters the diner to find the two staff members and a patron dead with their throats slit. Sam is missing and on the back door, Dean finds sulfur, meaning it was a demon attack.