The Denver Museum of Nature and Science made a surprise discovery during a project on the museum’s parking lot: a 70 million-year-old dinosaur fossil.

Coring research team members Denver Museum of Nature and Science

The fossil was discovered in January as the museum was conducting a drilling project to determine if it could transition from natural gas to geothermal energy. While the test was underway, the team took the chance to carry out scientific coring research to study the geology of the Denver Basin.

Around 763 feet below the surface, the team made an amazing discovery: the oldest dinosaur fossil ever found within the city limits.

Dinosaur fossil found during coring research project Denver Museum of Nature and Science

“This is a scientifically and historically thrilling find for both the museum and the larger Denver area,” said the museum’s Curator of Geology, James Hagadorn. “This fossil comes from an era just before the mass extinction that wiped out the dinosaurs, and it offers a rare window into the ecosystem that once existed right beneath modern-day Denver.”

The museum’s Director of Earth and Space Sciences, Patrick O’Connor, said the partial-bone fossil is a vertebra of an herbivorous dinosaur dated to approximately 67.5 million years ago.

Fossilized vertebra of dinosaur discovered under Denver Museum of Nature and Science parking lot Denver Museum of Nature and Science

“In my 35 years at the museum, we’ve never had an opportunity quite like this, to study the deep geologic layers beneath our feet with such precision,” said Earth Sciences Research Associate Bob Raynolds. “That this fossil turned up here, in City Park, is nothing short of magical.”

The fossil is now on display in the museum’s “Discovering Teen Rex” exhibit.