Along parts of Spain’s Costa Brava, sandstone cliffs display honeycomb-like patterns—small pits, rounded cavities, and tiny chambers arranged across the rock face. These patterns look almost carved, but they form naturally through a process known as tafoni weathering, shaped by salt, moisture, and wind.
The cliffs are composed of porous sandstone that easily absorbs moisture from sea spray. When salty water enters the tiny spaces within the rock, it evaporates, leaving salt crystals behind. Over time, these crystals expand and put pressure on the rock’s internal structure. This gradually loosens individual grains and weakens small sections of the surface.
Wind plays the next role. Strong coastal gusts remove the loosened grains, deepening some areas faster than others. Because the sandstone absorbs moisture unevenly, certain patches weaken more quickly, leading to clusters of tiny depressions. As this repeats across seasons, the depressions widen and form interconnected pockets that resemble honeycombs.
Coastal humidity keeps the process active, especially where shade prevents quick drying. Sun-exposed surfaces behave differently, creating a mix of shallow pits and deeper chambers. The result is a natural mosaic of textures and shapes formed without human intervention.
These honeycomb patterns are not unique to Spain, but the Costa Brava’s combination of sandstone cliffs, salty air, and steady winds makes them especially striking. Each pattern is the product of thousands of micro-changes, recorded in stone.