Adult T. rex trackway uncovered in North Dakota Badlands

Scientists working in the Hell Creek Formation near Marmarth, North Dakota, have documented a sequence of four three-toed footprints extending more than 23 feet, which they attribute to an adult Tyrannosaurus rex that lived about 66.5 million years ago. The find, published in the Journal of Vertebrate Paleontology, marks the first described adult T. rex trackway, although isolated prints have been reported previously.

The prints, each roughly three feet long, were uncovered on federal land managed by the U.S. Forest Service in 2025. Researchers used high-resolution 3D scanning to record the footprints and estimate the dinosaur’s stride at about 13 feet, suggesting a walking speed of 3.5 to 4.5 miles per hour.

"Initially I wasn't convinced because it was only one print," said Tyler Lyson, senior curator of vertebrate paleontology at the Denver Museum of Nature & Science. "If there's three, that's a pattern. If we can find a third print, then I'll be a true believer."

Lyson and volunteer Kent Hups later uncovered a third and then a fourth print within minutes of further excavation, confirming the trackway. A fifth print was discovered during a later field season. The team plans to recover three of the tracks in October for cleaning and analysis, hoping to reveal possible skin impressions that could clarify the shape of a T. rex foot.

Lead author Peter Falkingham, a paleobiology professor at Liverpool John Moores University, analyzed the 3D data remotely, contributing to the identification despite not seeing the tracks in person.