Located in northeast Africa, Eritrea is bordered by Sudan to the northwest, the Red Sea to the north and east, Djibouti in the southeast and Ethiopia to the south. The country's coastline stretches over 1,000 kilometres along the Red Sea.
Eritrea can be divided into three main regions: the central highlands, the western lowlands and the eastern escarpment and coastal plains. The capital city of Asmara is located in the central highlands, which is a narrow strip of land running through the middle of the country about 1,980 metres above sea level, and accounting for a fourth of the country's total area. Seasonal rivers and streams drain the highlands, and over the centuries flowing water has dug deep gorges and formed small, flat-topped tablelands called emba. The highlands receive the most rainfall, with an annual average of 40 to 60 centimetres; the region's fertile soil and favourable climate (averaging 18°C) make it the most populated and cultivated area in the country.
To the north and east, the highlands become narrow and hilly. The plateau drops into a coastal plain with poor soil and little vegetation. Accounting for a third of the country's total land area, the plain is only 15 to 80 kilometres wide in the north. In its southernmost section, the plain widens to include the Denakil Plains, a barren region that contains both the Denakil Depression, one of the hottest places on earth, and the Kobar Sink, a depression that descends more than 300 kilometres below sea level. The Sink is one of the lowest places in the world not covered by water.
The western flank of the central highlands is a broken and undulating plain that slopes toward the Sudan border. The sandy soil retains little water, and vegetation consists mostly of scattered trees, shrubs and grasses. Typical wildlife in Eritrea's hot savannah areas includes wildcats, warthogs, gazelles and jackals.
Off the east coast in the Red Sea is the Dahlak Archipelago, a group of more than 300 small islands, only a few of which are inhabited. The islands are home to a large number of nesting sea birds, including the Arabian bustard and osprey. In the sea lives the dugong or sea cow, a mammal that measures up to four metres in length and can weigh 1,000 kilograms. In ancient times, dugongs were mistaken for mermaids and gave rise to many legends.