A set of 200-million-year-old dinosaur footprints has been discovered at an elementary school, Ancient Origins reported.

The remarkably rare discovery has been residing at a small school in Queensland, Australia’s Banana Shire for the last 20-odd years, waiting to be discovered. Recently, school officials became curious about a pattern of tightly clustered footprints and asked University of Queensland paleontologist Anthony Romilio, who’s also known to be a successful fossil hunter, to take a look at the peculiar formation.

But Romilio was unprepared for what he was about to discover. The relatively small rock contained “one of the highest concentrations of dinosaur footprints” ever found in Australia. “It’s an unprecedented snapshot of dinosaur abundance, movement, and behavior from a time when no fossilized dinosaur bones have been found in Australia,” Romilio explained. “Significant fossils like this can sit unnoticed for years, even in plain sight. It’s incredible to think that a piece of history this rich was resting in a schoolyard all this time.”

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Romilio posited that part of the reason why the rock was left undisturbed for so long was because many likely assumed the dinosaur footprints, which number 66, were faux. “Some of the teachers thought this was a replica rather than the real thing,” he said. “Everyone didn’t quite realize what they actually have. They definitely knew it was a dinosaur footprint. But not the level of detail that a researcher like myself would go into.”

After extensive studies and test to track dinosaurs’ movement throughout the region, Romilio and his colleagues determined that the tracks belonged to a dinosaur known as Anomoepus scambu. “Dinosaur footprints have been reported from the Lower Jurassic Precipice Sandstone of the Callide Basin, Queensland, for over three decades, yet only a single track has been described until now, “ Romilio explained. “This study reports additional tracks on three ex-situ surfaces not previously described. These pedal impressions are assignable to the ichnospecies Anomoepus scambus.”

Following the identification of the dinosaur’s species, Romilio conducted several further experiments. Based on those findings, he hypothesizes that Anomoepus scambu’s hips were between eight and 30 inches wide and that they would not have walked faster than roughly 3.6 miles-per-hour. While Romilio expressed some surprise that the fossil had gone undiscovered for so long, he was hardly shocked. “The vast majority of dinosaur fossils, they’re not found by paleontologists,” he said. “They’re actually found by people on the ground.”