Brazil is the biggest country of South America, with an area of 8,547,404 km². It has 170 Million inhabitants and the Capital is Brasília. Other big cities are São Paulo, Rio de Janeiro, and Belo Horizonte. The language is Português.
Brazil is located around the equator, and most of its area is covered by tropical rain forrest. This area is called Amazonas, after one of the biggest rivers on Earth, the Amazonas river. But the southern part of the country is mostly hill country with numerous limestone karst areas.
Brazil is divided politically and geographically into five different regions which share common features:
Extremely rare is karst in little soluble rocks like sandstone and quartzite. But because of the high temperature and the high rain falls, this unique karst exists in Brazil in abundance. There are numerous quartzite karts caves in Minas Gerais which are show caves, and fantastic but not accessible cave in the Amazonas near Venezuela.
The Brazil cave cadastre, maintained by the Sociedade Brasileira de Espeleologia (Brazilian Society of Speleology), lists 4,300 caves . Not much, compared to the size of the country. About 100 new caves are discovered every year, but because of the difficult landscape and climatic conditions, the exploration is difficult and time-consuming. The longest cave system of Brazil is Toca da Boa Vista, which is 102,500 m long .