In area, Sudan is the largest country in Africa. It covers nearly one million square miles and extends between latitudes 3°N and 22°N and longitudes 22°E and 39°E. The country displays a wide range of geological and climatic features which much influence the structure of the economy and the course of its development. One third of the area consists of barren desert. Unfortunately it is these vast unproductive parts that lie close to the Red Sea coast, whereas the more productive regions are separated from the sea by distances which range between 500 and 1,500 miles. Their remoteness was a major factor retarding the development of the economy until the beginning of the present century when a network of railway and steamer lines was developed. Roads are still poor and undeveloped. Outside the towns there is only one short stretch of tarmac from Khartoum to the northern Gezira. The problem of relatively high transportation costs remains a major obstacle to a faster rate of economic growth and to a more even geographical distribution of development efforts.