Sauropoda
Pictures

Brachiosaurus, like other Sauropods, had massive, trunk-like legs.

Diplodocus and other sauropods had long, necks and small heads.

Camarasaurus and other Sauropods spent most of their lives in herds.

Apatosaurus and other Sauropods had long, whip-like tails.

Pictured next to a human for scale, it's easy to see how massive Brontosaurus and other Sauropods were, weighing as much as 65 tons.