PITTSBURGH: About 14 billion Big Macs have been flipped, bagged and consumed at McDonald's restaurants since a franchisee in the Pittsburgh area invented it in 1968.
To mark the Big Mac's place in fast-food history, McDonald's is launching an international celebration of its flagship burger.
The burger bash starts on May 4 in Pittsburgh where the mayor will proclaim the city of steel ''Big Mac City'' for a day.
However, Pittsburgh technically is not the Big Mac's birthplace.
That honour goes to Uniontown, Pennsylvania, where a McDonald's franchise owner introduced his original version of the double-deck hamburger in 1967 as an experiment to lure adult customers.
After sales of the burger took off, he introduced it at three other restaurants in the Pittsburgh area.
The corporate executives spotted a money-maker, refined the burger, got product approval from founder Ray Kroc - he was glad it lacked tomatoes, which he didn't care for - and unveiled it in 1968.