GIANT FINDING

Scientists Make Wild 66-Million-Year-Old Discovery in North Dakota

Researchers say this is the first uncovered trackway of an adult T. rex.

Scientists believe a recent discovery in North Dakota is the first known trackway left by an adult T. rex—66.5 million years after the dinosaur’s extinction. Researchers unearthed the footprint sequence in 2025 in the Hell Creek Formation of southwestern North Dakota and published the findings Sept. 9 in the Journal of Vertebrate Paleontology. At least four of the nearly 3-foot-long, three-toed footprints stretch more than 23 feet across the rocky terrain. While isolated footprints have been attributed to adult T. rex, researchers say this is the first uncovered adult T. rex trackway. “This is the first time scientists have described a sequence of tracks, or trackway, likely left by this most famous of dinosaurs,” the release said. The team returned to the site this summer and made another shocking discovery: a fifth track. “I have no doubt that if we were to continue to dig further into a hill that we would find more,” said Tyler Lyson, the senior curator of vertebrate paleontology at the Denver Museum of Nature & Science and the study’s co-author. “By cleaning these tracks, we might be able to have a better idea of what the actual foot of a T. rex looked like.”