History

Porto Velho
The capital of Rondônia owes its founding to the construction of the Madeira-Mamoré railroad at the beginning of the 20th century. It was originally planned to be built from Santo Antônio but the railroad was moved seven kilometers to a place called Porto Velho dos Militares as it had moorings for ships with deep draughts. It served as a base for troops at the time of the Paraguay War (1864-1870) as the Brazilian Emperor, Dom Pedro II, feared that Solano López (the former president of Paraguay) would send soldiers to attack Brazil by sailing down the rivers which formed the Amazon Basin. The municipality was founded officially in 1914 in the state of Amazonas and became the capital of the Territory of Guaporé (the future state of Rondônia) in 1943 with lands taken from the states of Amazonas and Mato Grosso. It measures 34,068.50 km² and is larger than the states of Sergipe and Alagoas. It has a population of 379,186 inhabitants, according to the official Brazilian statistics agency, the IBGE. The city of Porto Velho - the third-largest state capital in the North region - is located on the left bank of the River Madeira.

Santo Antônio do Alto Madeira
The Portuguese sailed along the River Madeira for the first time in 1650 in search of gold, precious stones and spices and to establish the limits of the territory of the Portuguese Crown. However, it was not until 1728 that the Jesuits, led by Father João Sam Payo, established a mission station in the region, raised on the first obstacle to existing navigation on the River Madeira, the waterfalls where the Santo Antônio HEP is being constructed. The mission was called Santo Antônio das Cachoeiras (Saint Anthony of the Waterfalls). After being attacked and destroyed in 1742by the Mura Indians, who inhabited the region, the place alternated between periods of occupation and abandonment and became a mere geographical reference point on the route between Belém-do-Grão-Pará and Vila Bela da Santíssima Trindade in Mato Grosso. At the beginning of last century, Santo Antônio had 3,000 inhabitants, with a mayor,  municipal council, judge and police chief. However, it was abandoned again after a decree by President Getúlio Vargas in 1943 under which it became part of the municipality of Porto Velho.