Rio Grande is a river in south-central Brazil. It rises in the Mantiqueira Mountains in the state of Minas Gerais and descends inland, west-northwestward. Its lower course marks a portion of the Minas Gerais-São Paulo border. At the Mato Grosso do Sul state border, after a course of 1,090 km, it joins the Paranaíba River to form the Upper Paraná River.
Major tributaries of the Rio Grande are:
Rio Aiuruoca, whose source is in Itamonte;
Wikipedia https://en.wikipedia.org/wiki/Rio_Grande_(Paraná_River_tributary)
Coordinates -20°40'11.095" N -46°19'3.11" E