Brazil is a federal republic in South America, a former colony of Portugal, the fifth largest country both in terms of area and population. It is bordered by Venezuela, Suriname and Guyana and French Guiana, by Colombia, Bolivia and Peru, Argentina and Paraguay. The southern part of Brazil is mainly upland, and the northwest is broad rolling terrain and low rounded hills.
The southeast of Brazil is more rugged with several mountain ranges, and drainage valleys of the eight major rivers, the largest being the Amazon, and the second largest river in the world. The climate shows a wide range of weather conditions but the largest part of the country is tropical, though different regions have microclimates that are very different.