Marathon is a chocolate bar consisting of an 8 inch length of braided chocolate covered caramel. It was manufactured by Mars Inc and first sold in the United States in August 1973. The bright red packaging had printed on it a ruler with inch (8) and cm (20) markings on the reverse demonstrating that it was as long as it claimed. (The length was the result of its braided shape; it did not weigh more than standard candy bars.) It was discontinued in October 1981. There was also a 15" version of The Marathon Bar sold in Southern California at local 7/11 stores and at Michael's Pharmacy in Swarthmore, Pennsylvania. These had a 15" ruler on the back of the red wrapper.
Another braided caramel and chocolate bar available from Cadbury's Curly Wurly candy bar. While these are commonplace in their native UK (as well as Australia), aside from specialty import stores (and World Market) Curly Wurly bars are not widely available in the U.S.