The D. Louis I Bridge (or Luiz I Bridge, in the original graph in it), is a bridge in metal structure with two boards, built between 1881 and 1886, connecting the cities of Porto and Vila Nova de Gaia (northern and southern bank, respectively) separated by the river Douro, in Portugal. This construction came to replace the old pencil bridge that existed in the same place and was carried out through the project of the Belgian engineer Théophile Seyrig, who had previously collaborated with Gustave Eiffel in the construction of the D. Maria Pia Bridge, a railway plant. The bridge was inaugurated in 1886 (upper board) and 1888 (inferior board and entrance in full operation). The D. Louis I Bridge has been classified as a Public Interest Real Estate since 1982 and as a UNESCO World Heritage Site since 1996.

The Arrábida Bridge is a bridge over the Douro River that connects Porto with Vila Nova de Gaia in Portugal. Since the 1930s it was necessary to create alternative connections to the old bridges (bridges D. Maria Pia and D. Louis) in order to respond to the growing flow of road traffic. At the time of its construction in 1963, the bridge had the largest armed concrete bow of any bridge in the world. The total length of the platform is 614,6m, having a width of 26.5m. Its 270 m, and 52 m of arrow, this bow consists of two paralel hollow ribs, 8 m wide linked to each other by longitudinal and transversal contraventation. It had two rolling tracks and two side tracks for pedestrians and cyclists. In the 1990s the number of road lanes was changed.

The River Douro (in Castilian: Duero) is a river that springs from the peaks of the Serra de Urbión, in the Spanish province of Soria, at 2,160 m altitude, and crossing northern Portugal to its foothills near the towns of Porto and Vila Nova de Gaia. It is the third largest river on the Iberian peninsula. It has a length of 897 km, 572 km in Spanish soil, 213 km navigable in Portuguese territory and 112 km of international character, because its course is border. This last stretch, in which the river narrows and its bed deepens, is known as the arribas. Its shores were protected with the creation of the Douro International Natural Parks in Portugal and the Arribas do Douro Natural Parks in Spain. On December 14, 2001, UNESCO included the Vinhateira Region of the High Douro (45°68' N, 5°93' W) in the list of sites that are a World Heritage Site, in the category of cultural landscape.

Ribeira is one of the oldest and most typical sites of the city of Porto in Portugal. Located in the parish of São Nicolau, next to the River Douro, it is part of the Historic Centre of Porto, UNESCO World Heritage Site. It is, at present, a very frequented area by tourists and a place of concentration of bars and restaurants. In Ribeira are well-known the Plaza da Ribeira, popularly also known as the square of the cube; Rua da Fonte Taurina, one of the oldest in the city; the Muro dos Bacalhaueiros and the Casa do Infante, where Infante D. Henrique is believed to have been born, in 1394. It was in this area of Porto that one of the most charismatic figures of the city lived, the so-called Duque da Ribeira, known for saving several people from drowning.

It is the city that gave the name to Portugal — from very early (c. 200 a.C.), when it was designated Portus Cale, and later became the capital of the Portuguese County, from which Portugal was formed. It is also a city known worldwide for its wine, its bridges and its contemporary and ancient architecture, its historic centre, classified as a World Heritage Site by UNESCO, the quality of its restaurants and its gastronomy. Porto, together with the neighbouring municipalities of Vila Nova de Gaia and Matosinhos, form the Atlantic Front of Porto, located on the coastline, delimited, to the west, by the Atlantic Ocean, with the structural influence of the Estuary of the River Douro.