Surrounded by a picturesque countryside in Spain, the crumbling stones of a convent hid a secret. Archaeologists were in for a surprise.

The convent of Santa Catalina del Monte in Cariñena thrived from the 1400s to the early 1800s. The building, however, fell into disrepair, according to a Tuesday, Jan. 31, news release from the Museum of Natural Sciences of the University of Zaragoza.

Archaeologists, led by Eduardo Díez de Pinos López, began excavating and restoring the site in 2021, museum officials said. During this excavation, a particular stone caught López’s attention.

The large limestone slab had an unusual indent on it, a three-toed shape that almost looked like a footprint. Photos from the museum show the tan-colored stone.

Archaeologists decided to investigate further and called in officials from the Museum of Natural Sciences of the University of Zaragoza. Looking at the stone, the scientists concluded this was a dinosaur footprint.

The footprint matched tracks from theropods, medium-sized carnivorous dinosaurs, experts said. The footprinted stone is estimated to be between 135 and 140 million years old.

The stone was likely used in the construction of a convent wall in the 17th to 18th centuries, experts said. The rock, however, did not come from the local area. It was most likely brought over from Villanueva de Huerva, a city about 10 miles west where similar dinosaur footprints have been found.

Restoration efforts are still underway at the 600-year-old convent. A Facebook video shared by Acrotera Heritage Management in August shows the ruins. A large portion of one wall still stands, but the rest of the site has been reduced to fragments.

Cariñena is about 175 miles northeast of Madrid.

Google Translate was used to translate the news release from the Museum of Natural Sciences of the University of Zaragoza. Facebook Translate was used to translate the post from Acrotera Heritage Management.

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