Nus de la Trinitat, Barcelona, Spain: Architect: Battle i Roig.

Enric Batlle, founding principal of Barcelona-based Batlle i Roig, believes landscape architects should not be afraid of to use the term "garden." Early in his career Batlle never used the word to describe his projects. He called them parks because he felt it elevated their status. But Batlle has embraced the notion of the garden, titling his book and recent lecture at the University of Virginia, "The Gardens of the Metropolis." The title is intriguing because it connects two scales: the intimate garden and the immense metropolis.

Batlle showed us a map of the edges between Barcelona's built environment and open spaces. His projects are bridges that connect the two. He presented a few examples of his work in Barcelona:

Trinitat Park (see image above) occupies an inaccessible location common to many major cities: the middle of a highway interchange. These spaces left over from large-scale infrastructure projects are almost uniformly forgotten. Here, his firm used rows of trees, grade changes, and a large circular "mountain" to sonically and visually shield the park from surrounding traffic.

The park acts as a bridge, allowing urban residents to access and enjoy previously inaccessible spaces. These kinds of bridges are increasingly necessary in growing cities searching for novel public spaces.

Batlle i Roig also worked on a landfill restoration project in El Garraf National Park completed in 2010 and located more than 10 miles from the center of Barcelona. Battle remains emphatic that the Garraf landfill reclamation project is in fact "urban public space" despite its distance from the city. It's urban because the park is filled with more than 40 years of Barcelona's waste. "What could be more urban than that?," he asked.

Garraf Waste Landfill, Begues, Spain / Battle i Roig

The space is public because a path switchbacks down immense terraces and eventually wanders into the city itself. The path defines the landfill as a public space, creating a sense of both accessibility and responsibility for the visitors confronted with the magnitude of urban waste production and management.

The Garraf Landfill Project demonstrates the radical nature of Batlle's theory of the garden's role in the contemporary metropolis. To garden is to cultivate and tend. By treating a landfill as a garden, Battle expands the traditional definitions of the term. Are landfills, highway interchanges, and other forgotten spaces that support the metropolis all potentially gardens?

This guest post is by Luke Harris, Master's of Landscape Architecture candidate, University of Virginia.