Andalusia is not only one of the bigger counties, it is also very rich in caves. There are several karst areas, some of which are protected by law.
This southern part of Spain is also famous for a long tradition of building cave houses, which is lately revived, because of the high costs of energy. The province of Granada has the largest cave dwelling population in Europe. Property developers have transformed hundreds of untouched or partly re-formed cave houses into modern holiday and second homes. Modern cave houses are much larger than the old ones, having ten or more rooms. There are three separate concentrations of cave houses, the historic Albaycin and Sacromonte neighborhoods of Granada City, Guadix and Baza. The Albaycin and Sacromonte are adjacent hillside neighborhoods, both of which form part of a UNESCO World Heritage Site along with the Alhambra Palace.