Archaeologists in North Dakota have unearthed the first set of footprints of a running T-Rex — after a schoolteacher led them to the “incredibly rare’’ find.

The four giant three-toed footprints of a massive 66-million-year-old T-Rex cover 23 feet and were found in the Hell’s Creek Formation in the state’s Badlands, The Sun reported Friday.

“Bones tell us an enormous amount about these animals, but footprints capture a moment of behavior,” said Tyler Lyson, senior curator of vertebrate paleontology at the Denver Museum of Nature & Science, to the outlet.

“With a trackway, we can actually follow an animal as it moved across the landscape.

“That is incredibly rare for T-Rex,” Lyson said.

The footprints measure about 3.3 feet per step.

Single T-Rex footprints of both fully grown and juvenile dinosaurs have been discovered before, but the North Dakota discovery marks the first time continuous tracks have been identified.

The fossils were found by Colorado schoolteacher Kent Hups, who co-authored a paper advising students that “science starts with curiosity, passion and careful observation.

“I never imagined that could lead me to a discovery like this,” Hups told The Sun.

Scientists also found T-Rex skeletal remains in the area, outlet said.

The tracks are now scheduled to be airlifted by helicopter and transported to the Denver museum.