The joint venture of Ferrovial and Portuguese contractor Alberto Couto Alves has finished the €99m extension of Porto Metro’s Yellow Line.

Portugal’s infrastructure minister Miguel Pinto Luz attended the inauguration ceremony on 28 June with environment and energy minister Maria da Graça Carvalho.

Over 36 months starting in 2021, the joint venture built a new 3.15km section of light rail to extend the Yellow Line from Santo Ovídio station to the south of the city.

Work involved building a 770m-long tunnel, three new stations, and a 430m-long viaduct between Santo Ovídio and the new Manuel Leão station.

Ferrovial said the viaduct was “one of the most complex parts of the project”.

The metal latticework structure on piers up to 22m high traces a 430m-long curve.

Owing to the difficulty of erecting it with cranes from the ground, the 2,746-tonne structure was slid into place from one end.

Its assembly took 143 days of work around the clock, involving 77 people, Ferrovial said.