In 2009, the world's largest dinosaur tracks were discovered in the French village of Plagne, in the Jura Mountains. Since then, a series of excavations at the site has uncovered other tracks, sprawling over more than 150 meters. They form the longest sauropod trackway ever to be found. Scientists have concluded these tracks were left 150 million years ago by a dinosaur at least 35 m long and weighing no less than 35 tons.

Source: World’s longest sauropod dinosaur trackway brought to light