Cosquer Cave: The Underwater Painted Cave near Marseille

The Cosquer Cave is a decorated Ice Age cave near Marseille, in southern France, whose only entrance now lies deep under the Mediterranean Sea. Its walls carry hand stencils and paintings of horses, seals and great auks made between roughly 33,000 and 19,000 years ago, when the sea was far lower and the cave stood on dry land. Revealed to the public in 1991, it is the only known decorated cave of its kind with an underwater entrance, and it is slowly being lost to rising waters.

Background: a coastline far from the sea

The cave lies in the Calanques, the steep limestone inlets of the coast between Marseille and Cassis. Today its entrance is a tunnel opening about 37 metres below the surface of the sea, at the foot of a cliff near Cap Morgiou.

During the coldest part of the last glacial period, around 20,000 years ago, so much water was locked up in ice sheets that world sea levels were roughly 120 to 135 metres lower than today. The coast near Marseille then lay several kilometres further south, and the cave mouth opened onto a coastal plain. People could walk into the cave on foot.

As the ice melted after about 19,000 years ago, the sea rose and gradually flooded the entrance and the lower chambers. The upper parts of the cave remained above water, trapped in an air pocket, which is why some of the art survives.

Discovery by Henri Cosquer

Henri Cosquer, a professional diver who ran a diving school in Cassis, found the entrance to the underwater tunnel in 1985. Over later dives he followed the narrow passage, more than 100 metres long and rising gradually, until he surfaced in large chambers partly filled with air.

Cosquer first kept the find quiet. In July 1991 three other divers died after becoming lost in the tunnel, a tragedy that showed how dangerous the cave was. In early September 1991 Cosquer reported the paintings to the French maritime archaeology authorities. Experts, including the prehistorian Jean Clottes and the archaeologist Jean Courtin, examined them and confirmed that they were genuine. The entrance was then sealed to prevent further accidents and damage.

At first some specialists doubted the find. The art was unexpectedly far from the main known centres of cave painting, and an underwater cave seemed an unlikely place for genuine Ice Age images. The doubts faded once radiocarbon dates on charcoal from the paintings came back from laboratories in 1992 and later, giving ages that matched the Upper Palaeolithic. Microscopic study of the paint and of the calcite on the walls also supported the paintings’ great age.

The art of Cosquer Cave

The art falls into two broad groups. The first consists of hand stencils, made by blowing or spraying pigment around a hand placed on the wall, and many lines traced with fingers in the soft surface of the rock. Dozens of hand stencils have been recorded, most of them in black, some in red. In a number of them fingers appear shortened. Researchers debate whether this reflects folded fingers, used as a kind of sign, or the loss of fingers through injury or frostbite.

The second group consists of animals painted in black or engraved into the rock. Well over 100 animal figures are known. Horses are the most common, followed by ibex, chamois, red deer, bison and aurochs. There are also a giant deer (megaloceros), a saiga antelope, and a possible cat.

Animals of the sea

What makes Cosquer unique among Ice Age caves is its sea creatures. Several seals are painted on the walls, along with fish and three birds generally identified as great auks, large flightless seabirds sometimes loosely described as penguins. Some researchers have also suggested that certain shapes represent jellyfish or octopus, though these identifications are uncertain.

These images show that the people who decorated the cave knew the marine life of a colder Mediterranean, when Atlantic species such as the great auk lived along its shores. One engraved human figure, apparently pierced by a line, has been compared to a similar figure at other caves and is sometimes called the “killed man”, but its meaning is unknown.

Dating

Radiocarbon dates on charcoal from paintings and from the cave floor indicate at least two phases of human visits. The hand stencils and finger tracings belong to the older phase, roughly 33,000 to 27,000 years ago. Most of the animal paintings belong to a later phase, roughly 24,000 to 19,000 years ago. The exact ages depend on calibration methods, so published figures vary.

The cave therefore spans the Gravettian and Solutrean periods of the Upper Palaeolithic. It is somewhat younger than the earliest art of Chauvet Cave and older than the famous paintings of Lascaux.

The threat of rising seas

Since the end of the Ice Age, the sea has flooded most of the cave. Researchers estimate that around four-fifths of the original surface is now under water, and any art in those parts has been destroyed or worn away. What survives lies in the upper parts of the chambers.

The sea level in the Mediterranean is still rising, at a rate of a few millimetres a year, and the water inside the cave also moves with tides, storms and air pressure. Plastic waste and pollution have reached the cave, and the walls near the waterline are being eroded. Archaeologists have warned that much of the remaining art could be lost within the coming decades.

For this reason, the French Ministry of Culture has carried out detailed 3D surveys of the cave, led by specialist divers including Luc Vanrell. The aim is to record every image digitally before it disappears, so that the cave can be studied and reconstructed even if the original is lost.

Cosquer Méditerranée

In June 2022 a full-scale reproduction called Cosquer Méditerranée opened in the Villa Méditerranée, a building on the Marseille waterfront. Based on the 3D surveys, it reproduces the main painted panels, including the horses, seals and great auks. Visitors move through the replica in small vehicles, in a setting designed to suggest the flooded cave.

The replica allows hundreds of thousands of people to see art that only a few divers have ever seen in person. It also raises public awareness of how climate and sea level change can threaten archaeological heritage, a theme linked to the wider story of Ice Age extinctions.

Timeline

• c. 33,000–27,000 years ago: First phase of visits; hand stencils and finger tracings are made.
• c. 24,000–19,000 years ago: Second phase; most of the animals, including seals and great auks, are painted.
• After c. 19,000 years ago: Melting ice sheets raise sea levels, gradually flooding the entrance.
• 1985: Henri Cosquer discovers the underwater tunnel entrance.
• 1991, July: Three divers die after getting lost in the cave.
• 1991, September: Cosquer reports the paintings; experts confirm their authenticity.
• 2022, June: The Cosquer Méditerranée replica opens in Marseille.

Why it matters

The Cosquer Cave shows that Ice Age art was not limited to the famous valleys of the Dordogne and northern Spain but also flourished on the Mediterranean coast. Its seals and great auks are unique records of a lost marine world. And its slow drowning is a striking reminder that sea level change, past and present, can erase entire chapters of human history.