Caves of Nerja

The first thing you notice is the air. Just past the entrance, the dry heat of the Andalusian hills falls away. The air turns cool and damp, and it smells faintly of wet stone. Your footsteps sound different here. They are softer, and they echo back from somewhere far above. Somewhere a single drop of water lands, and the sound carries across the dark. Welcome to the Caves of Nerja, one of the great underground landscapes of southern Spain.

Before we go deeper, let us start with how this place was found. It was January 1959. A small group of boys from the nearby village of Maro went out looking for bats. They had heard the animals came and went through a narrow sinkhole in the hillside, a spot locals called La Mina. The boys squeezed through the gap, lowered themselves into the dark, and found something no one alive had seen. Behind them, it turned out, lay an enormous hollow inside the mountain.

Think about that for a moment. These were not scientists or explorers. They were local teenagers with a light and a lot of curiosity. Some of them later described the bones and pottery they saw scattered across the floor. Those remains turned out to be the first sign of something remarkable. People had been inside this cave long before. Over thousands of years, they had sheltered here, cooked here, and buried their dead here.

So how did a space this size form? The answer is patience, and water. The mountain is made of marble and limestone. Over a very long time, rainwater picked up a little carbon dioxide from the air and soil. That made it slightly acidic. As it seeped through cracks in the rock, it slowly dissolved the stone and carved out passages. Later, the same process ran in reverse. Water dripped into the open chambers and left tiny deposits of calcite behind, drop by drop.

Those deposits are what you see around you now. The formations that hang from the ceiling are stalactites. The ones that rise from the floor are stalagmites. When the two meet, they form a column. Some of the shapes here look like curtains, some like frozen waterfalls, and some like stacks of melted candles. Their colours run from pale cream to honey and rust. The warmer shades come from traces of minerals carried in the water.

As you walk the route, pay attention to the scale. The paths and staircases are built into the cave, and they lead you up and down through a series of large halls. Each hall has its own character. Some feel low and close, with formations near enough to study in detail. Others open out so far that the lights barely reach the ceiling. It is easy to lose your sense of distance down here. A formation that looks small can turn out to be taller than a house.

Here is the first surprise most visitors miss. What you see on the public route is only part of the cave system. Beyond these halls lie further galleries, often called the Upper and New Galleries. Most visitors never enter them. They are protected because they are fragile and difficult to reach. Researchers and small specialist groups have explored them, and the cave as a whole runs for several kilometres. You are walking through the accessible front rooms of a much larger house.

Now to the human story, which is just as deep as the geology. Archaeologists have studied this cave for decades. They have found evidence of people living and visiting here across many thousands of years, from the Upper Palaeolithic, the late Old Stone Age, through to the Neolithic and beyond. They have uncovered tools, animal bones, shells from the nearby coast, pottery, and human burials. For long stretches of prehistory, this was a home, a workshop, and a sacred place.

The cave also contains prehistoric art. There are painted marks, lines, and figures on the walls in parts of the system, many of them away from the public route. Here is the second surprise, and it comes with an honest warning. Some researchers have argued that a few red paintings of what may be seals are extremely old. They have suggested these could be among the oldest art in Europe, possibly linked to Neanderthals. Other experts disagree. The dating is still debated, and it remains an open scientific question.

Let us come back to the halls. The most dramatic is usually called the Hall of the Cataclysm. Its name comes from the huge blocks of fallen rock and collapsed formations scattered across the floor. At its centre stands an enormous column, built up over a vast stretch of time. It has often been described as one of the largest known cave columns in the world. Stand at the rail for a minute and let your eyes travel slowly from its base to where it disappears into the ceiling.

One more detail gives this place a very unusual second life. Not long after the cave opened to visitors in the early 1960s, it began hosting live performances. A music and dance festival has been held here for decades, with concerts staged inside one of the large chambers and, in more recent years, at an outdoor venue near the entrance. Ballet dancers and well-known musicians have performed here. Imagine the sound of strings or a human voice rising through this stone hall.

The cave is also a living environment, and that is why the rules matter. The air temperature and humidity stay fairly steady all year. Each formation is still growing, but very slowly. The oils on a single fingertip can stop that growth on the spot where you touch it. Colonies of bats still use parts of the cave, just as they did when the boys came looking for them. The lighting is kept gentle, and visitors are asked to stay on the paths to protect it all.

As you head back toward the entrance, take a last look around you. Listen for the drip of water. That sound is the cave still at work, adding another thin layer of stone to a formation that might take centuries to change in a way you could see. Then step back out into the light. Notice the warmth on your skin, the smell of pine and dry earth, and the blue line of the Mediterranean below. Somewhere beneath your feet, the dark halls carry on, quiet and patient.