In 2012, a rancher in Patagonia, Argentina reported finding fossils on his land. This is a common find in Argentina. But after 18 months of excavation, it led to a very uncommon discovery: a new species of titanosaur. And it is one of the largest dinosaurs ever found! This massive plant-eater lived about 100 million years ago. Today, a cast of this 122-foot-long titanosaur welcomes visitors to the fossil halls at the American Museum of Natural History.