High Quality Content by WIKIPEDIA articles! The Xaparu River is a river of Roraima state in northern Brazil. Roraima is the northernmost and least populated state of Brazil, located in the Amazon region. It borders the states of Amazonas and Pará, as well as the nations of Venezuela and Guyana. The population is 400,000 (2006) and the capital is Boa Vista. Roraima is the Brazilian state with the fewest municipalities, 15 in total. The climate of Roraima is tropical with an annual mean temperature of 26°C (78.8°F). The state's southern part is located in the Amazon rainforest, while the north has open grassland fields, and there is a small strip of savanna to the east.