Archaeologists have discovered a hidden gallery of ancient paintings deep within the Atxurra cave in northern Spain.

At least 70 cave paintings have been found at the site, which reveals the ‘final moments’ of the Upper Paleolithic, dating as far back as 14,500 years ago.

Images of animals cover the walls of the sanctuary, including one which shows a bison impaled by the many spears of ancient hunters.

Atxurra cave is situated 50km from the Basque city Bilbao, in a village called Berriatua.

Local officials now say that the site is considered to hold the largest number of ancient paintings in Basque Country.

The cave paintings were discovered by archaeologist Diego Garate and caver Iñaki Intxaurbe.

They span roughly 100 meters, and largely represent horses, bison, goats, and deer.

    

Garate made note of a particular bison during a recent conference, which was painted to show numerous spears sticking in its belly, according to EFE Futuro.

‘This poor guy is probably the most hunted animal in all of Europe,’ Garate said.

The caves were first discovered in 1929, and local authorities recruited cavers to conduct explorations in 2014.

But, it wasn’t until September of 2015 that the sprawling collection was discovered 300 meters into the cave, at about four meters above the ground along an expanse of dangerous ledges.

Over thousands of years, the ‘paintings,’ have faded to become barely visible to the untrained eye.

Researchers say they may once have contained black pigmentation from coal, and may have been scraped into the stone by artists using flint tools.

    

The pictures are remarkably consistent, the researchers say, and can be traced back to the Upper Paleolithic Period.

This era began roughly 40,000 years ago and lasted until about 10,000 years ago.

The researchers place the origin of the paintings at 14,500 -12,500 years old, toward the end of this period

During the Upper Paleolithic, humans began to take huge steps in cultural advancement, and were known to use tools made of stone, flint, and bone.

Along with this, the basic forms of art began to emerge, with early humans starting to express themselves through drawing, painting, and even music.

Cave paintings from this period have been found throughout northern Spain, including the ‘Hall of bison’ discovered at the Altamira caves in Cantabria.

Researchers will continue to explore Atxurra over the next few years, and the cave will remain closed to the public in hopes to preserve the findings.