Barosaurus is a genus of dinosaur belonging to the family Diplodocidae. It lived approximately 155 to 145 million years ago, during the Late Jurassic, in what is now North America. The first fossils of Barosaurus were discovered in the late 19th century.

Barosaurus was an enormous dinosaur, estimated to have reached lengths of up to 25 meters and a height of around 15 meters at the shoulders. It possessed a long neck and tail, characteristic of sauropods, which enabled it to reach vegetation at various heights. Its body was supported by robust and pillar-like legs, and its skull was relatively small in proportion to its body size.

The massive size of Barosaurus suggests a slow and deliberate gait, using its pillar-like legs for support and movement. Its long neck and tail provided balance and aided in locomotion. Despite its enormous proportions, Barosaurus was likely capable of rearing up on its hind legs to reach higher vegetation.