Yellow forest is a collaboration between Eliasson and landscape architect Günther Vogt. Two clusters of birch trees are placed within the gallery to create a forest-like gathering place with a path leading through it. The clusters are encircled by a ring of yellow monofrequency lamps that is suspended from the ceiling and shines up into the canopy of leaves above. The lights tint the treetops and surrounding space in a single wavelength of visible light, making viewers perceive all colours as shades of black, grey, and yellow. At the same time, the lights delineate the space of this pavilion of trees, creating a forest of artificial nature, a potential space of retreat within the museum.