A summer hike in the Italian Alps turned into an archaeological find for a couple who stumbled upon prehistoric footprints millions of years old.

Claudia Steffensen and her husband were walking when she noticed unusual markings on a rock.

“It was a hot day, and we sought refuge in the mountains,” Steffensen told the Guardian. “Returning, I spotted peculiar circular patterns with wavy lines on what seemed like a cement slab. Closer inspection revealed them to be footprints.”

After recognizing the markings, she sought expert opinion.

Steffensen initially sent a photo to a nature photographer friend.

The photographer contacted Cristiano Dal Sasso, a paleontologist at Milan’s Natural History Museum, who consulted other specialists, according to the Guardian.

Melting snow and ice revealed the footprints, identified as belonging to a prehistoric reptile.

Subsequent exploration uncovered hundreds more fossilized amphibians, insects, plants, seeds, and even raindrop imprints, as reported by the Guardian.

According to Smithsonian Magazine, the footprints date back to the Permian period (251-299 million years ago), predating the dinosaurs.

National Geographic notes this period ended with a mass extinction event, wiping out 90% of marine and 70% of land species.

“While dinosaurs didn’t exist, the creatures leaving the largest footprints must have been quite large—up to 2-3 meters long,” Dal Sasso stated, as quoted by the Guardian.

Steffensen expressed pride in contributing to the discovery, now known as “Rock Zero.”

“I’m very proud to have made a small contribution to science,” Steffensen told the Guardian.

Research continues, with some artifacts transferred to the museum in Milan for display.