The Santos-Guarajá Tunnel in the state of São Paulo will be approximately 1.5km long, with an 870m section beneath the access channel to the Port of Santos.
The R$7.8bn (US$1.42bn) public-private partnership contract covers a 30-year concession, with construction expected to take five years.
The tunnel will comprise three lanes in each direction, a line for light rail vehicles, cycle paths and areas for pedestrians.
The new crossing will reduce vehicle journey times from an hour to five minutes and boost the competitiveness of the Port of Santos – the largest in Latin America.
