Which one of these countries covers the largest total land area?

Among the countries of Chad, Nauru, Andorra, and Barbados, Chad is the country that covers the largest total land area. It is a landlocked country in North-Central Africa occupying an area of 1,284,000 sq. km. (496,000 sq. mi). In the northern reaches of the country, the Tibesti Mountains dominate the landscape of the surrounding Sahara Desert.

In the Sahel region, on the southern edges of the ever-expanding Sahara Desert to the north, there is a transition zone between the dry areas of the north and the tropical areas of the south. The country receives very little rain, and most of the vegetation is a savanna growth of sparse grasses and shrubs.

The land rises into the Ennedi and Wadai plateaus along the eastern border with Sudan, where elevations reach near 609 m (1,998 ft). In the south, the forested land is nourished by the Chari and Logone Rivers. Lake Chad is located in the center of the western frontier. It has an elevation of 281 m. (922 ft). During the monsoon rains, Lake Chad often overflows, causing floods in the lowland depression of the south.

The highest point of Chad is Emi Koussi, which rises 3,415 m (11,204 ft) in the northern mountains. The lowest point of the country is at the Djourab Depression, 160 m. (525 ft).

Noting Nauru, Andorra, and Barbados, respectively, the total land area for each of these countries is 21 sq. km (8.1 sq. mi); 467.63 sq. km (180.55 sq mi); and 439 sq. km (169 sq mi).