Famous for its massive malts and double-deck hamburgers, there were six Oscar’s drive-in coffee shops in San Diego where carhops - servers on roller skates - would bring food to your car.

Black and white photographs on the internet show the Oscar’s at El Cajon Blvd with candy striped awnings and - we’ve no idea why - a parade of elephants embossed on the entrance wall. Apparently, locals nicknamed it the ‘circus,’ due to the animal posters inside and out.

Robert O Peterson was a founder of the Oscars hamburger chain and later went on to create the Jack in the Box restaurant chain.

A native San Diegan, former traveling salesman and WWII intelligence officer, he founded Topsy’s drive-in in 1941 and it later became Oscar’s. In 1951, Peterson opened his first Jack in the Box and is credited with being the first to pair a drive-through with an intercom system. The speaker to take orders was hidden inside a plastic clown.

By 1967, with 300 Jack in the Boxes, Peterson sold the chain to the American conglomerate Ralston Purina, which later merged with Nestlé.

We’ve also found information about Oscar Soledad, a former chief of police of the town of Santa Cruz, who has been credited by some as being another founder of Oscar’s, along with his partner Stephen Ashley.

Ashley’s father Jack was also a fast-food pioneer, opening the first drive-through bakery on Point Loma in 1909, correctly guessing that people in automobiles wouldn’t want to get out of their cars and walk just to pick up bread.

There were six Oscar’s in San Diego at 12th and C streets, Midway and Rosecrans, Pacific and Rosecrans, Euclid and El Cajon, Mission Blvd and Garnet, Pacific Beach, and 16th and National, National City.

We believe this menu is from the late 1950s or early 60s when a double-deck hamburger cost 44c and the famous extra-rich, extra-thick malts and milkshakes topped with whipped cream cost 25c.