The Southeast Region of Brazil (; ) is composed of the states of Espírito Santo, Minas Gerais, Rio de Janeiro and São Paulo. It is the richest region of the country, responsible for approximately 60% of the Brazilian GDP, as São Paulo, Rio de Janeiro, and Minas Gerais are the three richest states of Brazil, the top three Brazilian states in terms of GDP. The Southeast of Brazil also has the highest GDP per capita among all Brazilian regions. The Southeast region leads the country in population, urban population, population density, vehicles, industries, universities, airports, ports, highways, hospitals, schools, houses and many other areas. Geography São Paulo Heart of the largest continued remnant of the Brazilian Atlantic Forest, the Ribeira Valley is a Natural Heritage of Humanity, granted heritage as a Biosphere Reserve by UNESCO. One of the biggest attractions is the biologic and ecosystems diversity, where approximately 400 species of birds, amphibians, reptiles and mammals live. The Alto Ribeira Tourist State Park (PETAR) is paradise for ecotourists, for its enormous diversity in geologic formations, among grottos and caves, rivers and waterfalls. There are currently 454 caves registered by the Brazilian Society of Speleology (SBE) in the State of São Paulo, all at the Ribeira Valley. The 280 caves located at PETAR represent the biggest concentration of caves in Brazil. Minas Gerais The landscape of the State is marked by mountains, valleys and caverns. In the Serra do Cipó, Sete Lagoas, Cordisburgo and Lagoa Santa, the caves and waterfalls. Minas Gerais is the source of some of the biggest rivers in Brazil, most notably the São Francisco, the Paraná and to a lesser extent, the Rio Doce. The state also holds many hydroelectric power plants, including Furnas dam. Some of the highest peaks in Brazil are in the mountain ranges in the southern part of the state, such as Serra da Mantiqueira and Serra do Cervo, which mark the border between Minas and its neighbors São Paulo and Rio de Janeiro. The most notable one is the Pico da Bandeira, the third highest mountain in Brazil at 2890 m, standing on the border with Espírito Santo state. The state also has huge reserves of iron and sizeable reserves of gold and gemstones, including emerald, topaz and aquamarine mines. Rio de Janeiro The state is part of the Mata Atlântica biome, and its topography comprises both mountains and plains, located between