As part of the 2021 celebration of A Cel Obert, a festival of ephemeral architecture held in Tortosa (Tarragona), this monumental-scale, over 6-meter-high lamp is the work of the architects Manuel Bouzas and Santiago del Águila, in collaboration with the lighting designer Ana Barbier. By means of a lightweight structure of wires and turnbuckles, the artistic installation hangs down from the cornice of the main courtyard of the Purissima Concepció Monastery. As the authors explain, the project arose from the double meaning of the word ‘Lucerne.’ On the one hand, the term defines the upper openings that serve to, bring natural light into indoor spaces. But it was used by the Romans to name the early oil lamps that produced light in the dark. Wrapped in a translucent skin of polyester resin, the installation is built with six wooden rings, and LED light strips are fastened to their inner edges. A small staircase lifts visitors to enter the lamp, where they are treated to the Cel Obert (open sky), framed by the geometry of the piece.