Scientists confirm first full-length walking track of adult Tyrannosaurus rex in North Dakota

A volunteer on a fossil dig in the Hell Creek Formation of North Dakota uncovered a continuous 23-foot trackway consisting of four massive three-toed prints, the first confirmed walking track of an adult Tyrannosaurus rex. The footprints, each about three feet long and two feet wide with a 13-foot stride, were found on federal land near Marmarth in July 2025 and were described in a recent issue of the Journal of Vertebrate Paleontology.

The discovery was made by Kent Hups, a Colorado high-school science teacher recovering from knee surgery, who recognized the lumpy sandstone as dinosaur tracks and measured them on site. Paleontologist Thomas Carr noted that after more than a century of fossil collection in the Hell Creek Formation, this find represents an early milestone in the region’s trackway record.

Senior curator Tyler Lyson of the Denver Museum of Nature and Science, who co-authored the study, confirmed the identification based on the size, toe shape, and the abundance of T. rex remains in the area. Prior to this, only two isolated T. rex footprints had been documented, one in Montana and another in New Mexico.

Researchers estimate the animal was moving at 3.5-4.5 mph, comparable to a human power walk. Evolutionary biomechanics professor John Hutchinson said the trackway provides rare insight into the gait of a large theropod during slow walking, though it does not indicate overall athletic ability.

High-resolution 3D scanning was used to create digital models of the prints, which will aid in producing physical replicas. The team has secured permits to excavate three of the heavy sandstone casts, each weighing up to 1,000 pounds, and will transport them by helicopter to the Denver Museum for cleaning and study. The museum plans to display the fossils and allow visitors, including Hups’ geology students, to observe the preparation process.

Lyson emphasized that the find demonstrates how amateur involvement can lead to significant paleontological discoveries, encouraging both students and the public to engage with field research.