The Museo a Cielo Abierto de Valparaíso (MaCA) is the result of a course of the Art Institute of the Universidad Católica de Valparaíso (UCV) and was concretized thanks to an agreement with the local Municipality, which allowed the intervention of the public space. Devised by the painter, architect and academic Francisco Méndez Labbé (1922-2021) in 1991 and inaugurated in July 1992, it had donated works elaborated by eighteen key references of Chilean art of the mid-twentieth century, installed in a circuit that Méndez defined in the central Bellavista hill. Between 1969 and 1973 Francisco Méndez developed a Mural Workshop where he went out with his students from the UCV to intervene in the walls of the city. In 1991 Méndez invited a wide spectrum of artists to send sketches. Finally, twenty-one works were incorporated, authored by Mario Carreño, Gracia Barrios, Eduardo Pérez, Matilde Pérez, Eduardo Vilches, María Martner, Ricardo Yrarrázaval, Rodolfo Opazo, Roberto Matta, Ramón Vergara Grez, Mario Toral, Roser Bru, Sergio Montecino, NemesioAntúnez, José Balmes, Guillermo Núñez, Augusto Barcia and Francisco Méndez. The stylistic diversity of the participants and their works make up an exhibition that can be considered a synthesis of Chilean painting of the mid-twentieth century.