Among the causes of this loss of population is the peculiar geography of Cádiz; the city lies on a narrow spit of land hemmed in by the sea. Consequently, there is a pronounced shortage of land to be developed. The city has very little vacant land, and a high proportion of its housing stock is relatively low in density. (That is to say, many buildings are only two or three stories tall, and they are only able to house a relatively small number of people within their "footprint".) The older quarters of Cádiz are full of buildings that, because of their age and historical significance, are not eligible for urban renewal.