The cave of Kakaviotissa is located in the area of Kakavos, northeast of the village of Thanos. To reach the cave, visitors must first ascend the volcanic hill of Kakavos made of andesitic lava. At the summit of the hill, weathering formations are visible. These are “tafoni,” which are cavities formed by the erosion of volcanic rocks. Today, the church of Panagia Kakaviotissa is constructed in the largest of these cavities.

The term “tafoni” is derived from the Corsican word for “window” and is used around the globe to characterize these distinctive honeycomb weathering patterns seen in granular igneous and sedimentary rocks. Their appearance is determined by the selective or differential erosion of the rock surface. Their formation is caused by rock characteristics (granular composition, strength, and lithology) as well as external effects from physical, biotic, and chemical variables.