08/10/2026
In Europe, cities are confronting the challenge of adapting existing urban conditions to a changing climate and warming summers while improving access to nature, quality public spaces, and the resources of everyday routines. ReGreeneration, a Horizon Europe initiative working across nine European cities, approaches this challenge through urban renaturing at the neighborhood scale. Combining strategies for complete neighborhoods, communal spaces, and nature-based solutions for cities, the Barcelona project examines how climate adaptation is embedded within residual, peripheral spaces of daily life. As part of a series following ReGreeneration across the participating cities, this article turns to Barcelona, where the project is working in the Trinitat Nova neighborhood to explore how small, often overlooked, urban spaces contribute to broader models of regeneration.
While many of Barcelona's well-known public space projects operate at the scale of major avenues, pedestrian streets, plazas, and parks, the city's PEPI program turns its attention to a more fragmented layer of the urban fabric. Introduced in 2024, PEPI focuses on proximity and interior spaces, identifying courtyards, vacant plots, block interiors, parking areas, rooftops, and other underused corners as opportunities for green and communal space. In a dense and largely built-out city, PEPI reframes these residual spaces as latent urban capacity, asking how areas overlooked by conventional planning might instead contribute to everyday life.
Image 21 of 22 from gallery of Designing the In-Between: From Tactical Interventions to Urban Policy in Barcelona. Photograph by Leku Studio
