Cyprus is, and has traditionally been, largely agricultural and rural in orientation. For historic and economic reasons, there are few coastal settlements—the island was often plagued by pirates, and the lack of fish meant that there was little Economic incentive for settling on the coast. Houses in the Villages are two-to four-room structures of sun-dried mud brick or stone, with long, flat roofs also made of mud. Village settlements were and remain ethnically exclusive, although in the cities such strict divisions necessarily broke down. Nonetheless, even in the cities, there tends to be a marked division into ethnically homogeneous enclaves. Some 40 percent of the population lived in the cities as of 1970, and that ratio has been steadily increasing.