The Dom Luis I Bridge is one of the most distinctive sights in Porto.
Image © Dias dos Reis
The road bridge links Porto with Vila Nova de Gaia and it's historic port wine lodges on two levels with the city's metro line now running on the upper tier, replacing the previous road crossing and cars and other vehicles on the lower tier.
There are stunning views for pedestrians from the upper tier.
The bridge was opened in 1886 and designed by a follower of Gustav Eiffel, who incidently built the Ponte de Dona Maria Pia railway bridge in Porto.