The Trinitat interchange is a complex road infrastructure located in the north-east of Barcelona, in an old meander of the Besòs river, next to the Trinitat neighbourhood. It meets the Ronda de Dalt, the Ronda Litoral and three motorways: the C-58, the C-33 and the B-20. It is also facing the Santa Coloma Promenade and the Trinitat neighbourhoodl located approximately twelve metres above the meander. The complexity of the road layout gives rise to an overlap of structures, passages at different levels and tunnels of up to fifteen metres between them in some places.
The basic objective was to order, develop and provide public content to the free spaces resulting from the construction of the interchange, as well as to relate these to the consolidated core of the Trinitat neighbourhood with the adjacent neighbourhoods (Santa Coloma de Gramanet, Sant Andreu del Palomar, La Sagrera etc.) through Santa Coloma Promenade and with the rest of the city, by means of a newly created Metro station.
Our work was based on a general consideration of the environment that allowed us to understand the treatment of the junction and the links with the motorway, not as a sum of various solutions, but from the perspective of a single project unit, where vegetation, hydraulics, topography, equipment and public spaces are governed from a single layout idea.
Of all the free spaces resulting from the layout of the interchange, without a doubt, the largest and most interesting was the central circle. About 300 metres in diameter, limited on its southern side by the train route, the Trinitat Park is located practically at the natural level of the meander.
The project assumes as its own objective to facilitate access to the interior of the park from the neighbourhood, by means of an access square through a connection below the infrastructures with the Santa Coloma Promenade and from the metropolitan area through the insertion inside of a Metro station that at the same time connects the different topographical levels with mechanical systems. The objectives were also to reduce both the visual and acoustic impact of the new roads on the neighbourhood and on the park itself, as well as fulfill an extensive program of equipment and services requested by the residents.
The geometry of the interchange becomes the project's layout instrument from which all areas of the program are developed: parking, sports facilities, promenade, amphitheatre, pond, paths and groves.
The species used in the plantations are the characteristics of the agricultural landscape in the immediate surroundings: cypress barriers in the Empordà, cornfields and banana fields in Girona, plots of olive trees in Tarragona or fruit trees mounted on metal structures in Lleida. The use of vegetation as a means of modifying the scale of the site is reinforced by a topography centered on a single formal effect: a spherical helmet-shaped hill that rises from the lowest level of the terrain to almost reach the height of highways. The plant alignments that follow the riverbank enter the park and go up the hill, accentuating its topography.
