During the last decades of the 20th century the increasing number of cars made Porto the scene of an almost continuos enormous traffic jam. The buses were stuck in the jam too. The remains of the old tram system, in decline since 1959, were not suited to provide a base for high capacity public transport. But Porto was considered too small for a full scale underground system. It was decided to create a new light-rail system in tunnels in the central area of the city and at surface outside the central area. For this a new organisation was created, the Metro do Porto.

From Porto to the North existed two narrow gauge railways. The oldest one went from Porto to Póvoa de Varzim. The second line diverted from the first in Senhora da Hora and went via Maia to Trofa and then on to Guimarães. This line connected in Trofa with the broad gauge Linha do Minho. The broad and narrow gauge lines continued together over a distance of 2.5 km until Lousado where the broad an narrow gauge railways diverted again. During the first years of the 21st century the section from Trofa to Guimarães was converted to broad gauge and together with the Linha do Minho electrified and modernised. Part of this modernisation project was a diversion of the broad gauge railway from the East to the West side of Trofa.

The remaining narrow gauge lines were handed over to the Metro do Porto to be incorporated in the light-rail network. This meant change of gauge from 1000 mm to 1435 mm, change to double track over the whole routes and electrification. Also more stops were added. Several of the old station buildings were made into cafés, shops or substations, while others became disused or were demolished.

The section between ISMAI and Trofa was part of the project but never realised. This is a rural area. The old narrow gauge line existed only because of the direct narrow gauge trains from Porto to Guimarães vv. However with the Guimarães line converted to broad gauge and the trains using the Linha do Minho from/to Porto, there is no need anymore for high capacity public transport between Porto and Trofa via Maia. Maia itself had grown into an important city into the Greater Porto area.

The Metro do Porto network

The network officially counts six lines indicated with A to F. However in practice the lines A and F make one line with most of the trams covering the whole of their combined routes. The dynamic information on the trams and the stations display the actual destination: already Fânzeres while still in Matosinhos and already Senhor de Matosinhos at departure from Fânzeres.

Characteristics

The network is extended over a number of different types of areas. This has made that the character of the system varies over the network. In the central part of the city tunnels are used. The stations in this area have the character of real metro stations. Passengers are not allowed to cross the tracks. This full metro character exists for all stations on the joint route from Estádio do Dragão up to and including Trindade, for all stations on the tunnel part of line D and for the Casa da Música (joint route), Sto.Ovídio (line D) and Nau Vitória (line F) stations. On all other stations and stops passengers are allowed and in most cases have to cross the tracks at level.

The remaining part of the joint route and most of the lines B and C have no level crossing with other traffic than pedestrians. On the lines B and C are a few railway type automatic half barrier crossings.

In the suburban areas of Matosinhos (line A), VN de Gaia (line D) and Gondomar (line F), but also in the build-up areas of Vila do Conde, Póvoa de Varzim (both line B), Maia (line C) and near Hôspital de São João (line D) and Botica (line E) the tracks are on reserved space, often in the central or aside of roads, with traffic lights securing road crossings.

In the centres of Matosinhos (line A) and Maia (line C) are streets where the trams share the space with pedestrians. This is also the case on the top deck of the Ponte Luís I and the adjacent area of Jardim do Morro.

The different lines of the network are described on separate pages:

• The joint route
• Line A
• Lines B (Maia part) and E
• Line B in Vila do Conde and Póvoa de Varzim
• Line C
• Line D
• Line F

Future

The success of the Metro do Porto resulted in ambitious plans to extend the system, though difficult economical and financial problems have put realisation of these plans on hold until funds became available in 2016. Under construction (status 2022) are:
Extension of line D in Southern direction from Sto.Ovídio to Manuel Leão – Hospital Santos Silva – Vila d’Este. This extension will be 3.1 km long of which about 600 m on viaduct, 1100 m in tunnel and 1400 m at surface. The Manuel Leão station will be underground, both others at surface. Between Hospital Santos Silva and Vila d’Este a depot will be made for about twenty trams with equipments for cleaning and maintenance as well as accommodation for staff.
New line G in the central area of the city: Casa da Música – Galiza – Hôspital Sto.António – Liberdade (São Bento) This line will be about 2.7 km long and fully underground. At Casa da Música a connection will be made with the joint route for depot trips. Between Liberdade and the existing São Bento station of line D a pedestrian tunnel will be made for easy changing.

Another new line (H) is in the development phase. It will go from Casa da Música via Devesas to Sto.Ovídio. For this line a new bridge across the Douro will be constructed near Massarelos. Next on the list is a new line from Campanhã to Gondomar (Souto).

Rolling stock

The MP has two types of trams, both made by Bombardier. Operations started with Eurotrams, a 100% low floor type that Bombardier inherited from ABB/Adtranz and branded as one of the Flexity Outlook models, although the production was discontinued later. There are 72 units, which are used on the lines A, D, E and F. During peak hours they also see service on line C. Each tram is 35 m long and 2.65 m wide. The maximum speed is 80 km/h and they can go through curves with a radius of 18 m. They can be coupled to a maximum of two units.

For the longer routes the MP acquired 30 trams of the Flexity Swift type. These trams are 37 m long and 2.65 m wide. The maximum speed is 100 km/h and the minimum radius 25 m. Their low floor range is 70%. They are used on the lines B and C and can be coupled to a maximum of two units.

In 2023 18 trams from the Chinese firm CRRC Changchun Railway Vehicles will enter service.