The country covers an area of 677,000 square kilometres (261,228 square miles) ranging 936 kilometres (581 miles) from east to west and 2,051 kilometres (1,275 miles) from north to south, It is a land of hills and valleys and is rimmed in the north, east and west by mountain ranges forming a giant horseshoe. Enclosed within the mountain barriers are the flat lands of Ayeyarwaddy, Chindwin and Sittaung River valleys where most of the country’s agricultural land and population are concentrated.