5 September 2014. This is the first commercial installation in the world of the Aeromovel design, an atmospheric railway technology first developed in Porto Alegre in the late 1970s. Future expansion Line 2 of the metro is proposed to consist of a route from the city centre to Cachoeirinha, of which around half will be underground. In 2019, the estimated cost of the line was $2.9 billion. Network Map See also List of metro systems Rapid transit in Brazil References Metro Rapid transit in Brazil Underground rapid transit in Brazil Transport in Rio Grande do Sul Electric railways in Brazil 3000 V DC railway electrification