Echoes & Evolutions: Nancy Holt’s Sun Tunnels was presented at Sprüth Magers, New York from September 5 to October 25, 2025. The exhibition focused on Sun Tunnels (1973–76), a landmark work in Nancy Holt’s oeuvre that encapsulates her sustained investigation of perception, systems, and site. Featuring many previously unseen drawings, collages, photographs, and two Studio Locator sculptures, the exhibition offered insight into the conceptual and material processes behind the creation of Sun Tunnels.

Based on precise calculations, the concrete tunnels were positioned to frame the rising and setting sun during the summer and winter solstices. Circular perforations puncture their surfaces, allowing sunlight and moonlight to project specific star constellations into the tunnel interiors. Works on paper, such as Drawing for Positioning of Holes in the Perseus Constellation for One Tunnel of "Sun Tunnels"  (1975) served as studies for these perforations. In selecting the constellations—Draco, Perseus, Columba, and Capricorn—Holt chose star groupings of varying magnitude, enabling the work to be experienced both from within and from outside the tunnels.

Holt’s process also involved making cardboard tube models, which she photographed to study scale, orientation, and the shifting behavior of light and shadow. In these 1975  photo studies, she tested different configurations and constellation patterns, annotating the backs of the photographs with notes on time, alignment, and celestial reference. Through this expansive series, patterns in her practice emerge that illustrate her systematic approach to making sculpture. This is emphasized again in Sunlight in Sun Tunnels and Sun Tunnels: Shifting Shadows (both 1976) in which Holt charted the evolving light and shadow at regular intervals over the course of one day respectively, bringing together the process into a single photographic composite.

Also on view were two Studio Locators, Holt’s first sculptures made in 1971 and direct precursors to Sun Tunnels. Constructed from steel pipe and mounted at eye level, the Locators function as lensless viewing devices that frame specific fields of vision. Originally oriented toward architectural details visible from Holt’s Greenwich Street studio in New York, these works foreground her interest in directing perception and revealing the sculptural qualities of often-overlooked systems within the built environment. Locator (Exhaust Pipe) looks up to a roof ventilation pipe, while Locator in Window—the first of her Studio Locators—focusses vision on a single point directed by the Locator.