Mario Merz is a senior artist of the postwar Italian movement known as Arte Povera. The phrase arte povera literally means "poor art" and was coined in 1967 to describe the work being created by a loose-knit group of artists residing primarily in Milan, Rome, and Turin. These artists were determined to question the boundaries between traditional artistic practices (painting and sculpture) through the use of nontraditional materials (i.e., lead, glass, vegetation, newspaper, fabric) in an effort to align their work more closely to the worlds of science and nature.
In 1972, Mario Merz had his first American museum exhibition at the Walker Art Center. Twenty-five years later, in July 1997, his untitled commission was installed on the roof of the Conservatory. Constructed of clear glass and infused with pure red neon gas, the work reads citta irreale (unreal city), which is a recurring phrase in T.S. Eliot's poem The Waste Land. Merz uses citta irreale as a metaphor for the world of art as a "city of ideas." The neon is intended to function like a beacon inviting those rushing to and fro in the real city (outside the limits of the Garden) to pause for a moment and perhaps enter the unreal city where reflection, contemplation, and renewal of the spirit are the goals.