Polje de la Nava

A polje is a large, enclosed, elongated depression with a flat floor found in karst terrain.

This polje has both tectonic (involving a thrust fault and subsidence of the land) and karstic (rock dissolution) origins. It lies at an altitude of around 1,000 metres and is of medium size among the poljes of Andalusia, measuring 7 km in length and 1 km in width. For much of the year, water drains into the subsoil in a diffuse manner, through cracks in the floor and via a sinkhole that suddenly appeared in 2012. During the rainy season, due to the low permeability of the clays at the bottom, La Nava de Cabra tends to flood, and on occasions the sinkhole is unable to cope with the volume of water and becomes submerged.