The Republic of Peru, located in west central South America, is bounded on the north by Ecuador and Colombia, on the east by Brazil and Bolivia, on the south by Chile and on the west by the Pacific Ocean. The area of Peru, including several offshore islands, is 1 285 220 km2. The country can be divided into three natural regions coastal, mountain and forest.
The coastal region is a narrow strip over 3 000 km long with an average breadth of 60 km, bordered on the west by the Pacific Ocean and on the east by the mountains. It is for the most part an arid zone, with good-quality farmland only in the valleys formed by the 52 seasonal rivers that flow into the sea.
The mountain region, or sierra, is the second largest natural zone in the country. Narrow valleys and plateaux make up much of the region. The main mountain range is the Cordillera Occidental; other ranges include the Cordillera Oriental, the Cordillera Central, and a number of lesser chains. Bordered on the west by the coastal region and on the east by the Peruvian forest, this is traditionally a farming region and has always suffered major demographic pressure, so that areas suitable for forest use have been turned to agricultural use. Several of the highest peaks in the world are located in the various sierras, cordilleras and plateaux, notably Huascarán (6 768 m), the highest point in Peru. Lake Titicaca lies to the south-east. Earthquakes occur frequently.
The forest region, or selva, is the largest and most sparsely populated in the country. Bordered on the west by the mountains, it stretches to the borders with Ecuador, Colombia, Brazil and Bolivia. Physiographic, floristic, edaphic and socio-economic conditions permit this natural region to be classified as high forest and low forest. The high forest is the belt lying between 3 600 m on the eastern slope of the Peruvian Andes (on the border with the mountain region) down to 700 m. Altitudes above 2 500 m in this subregion are usually called "forest rim". The broad Amazon plain the low forest is the least populated zone, not only of the forest region, but also of the whole country, so that its original features are still relatively intact.
The climate of Peru varies widely, ranging from tropical in the east to arctic in the highest mountains of the Andes. In the coastal plain the temperature normally averages about 20° C throughout the year. The coastal climate is moderated by winds blowing from the cool offshore current known as the Peru, or Humboldt, Current. The coast receives less than 50 mm of precipitation each year, largely because the cordilleras receive most of the rain carried by the trade winds from the east. Mist-laden clouds known as garúa shroud many of the slopes of the sierra from June to October, providing enough moisture to support grasslands. In the sierra the temperature ranges seasonally from about -7° to 21° C. Rainfall is usually scanty, but in some localities heavy rains fall from October to April. In Cusco, in the south-eastern sierra, annual rainfall averages some 815 mm.
The selva is extremely hot and humid, although moderated at higher altitudes. The prevailing easterly winds blowing across the region gather moisture that is later deposited on the eastern Andean slopes. Annual rainfall in some districts averages as much as 4 000 mm.
The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.