Double Torqued Ellipse, 2003-2004. Weathering steel, outer ellipse: 14' x 37'5" x 40' (4.27 x 11.41 x 12.19 m); inner ellipse: 14' x 20'4" x 32' (4.27 x 6.2 x 9.75 m); plate thickness: 2" (5 cm). Guggenheim Bilbao Museoa  GBM2004.7. © 2012 Richard Serra/Artists Rights Society (ARS), New York. Photo: Erika Barahona-Ede

Richard Serra has long been acclaimed for his challenging and innovative work, which emphasizes the process of its fabrication, characteristics of materials, and an engagement with viewer and site. In the early 1960s, Serra and the Minimalist artists of his generation turned to unconventional, industrial materials and began to accentuate the physical properties of their work. Relieved of its symbolic role, freed from the traditional pedestal, and introduced into the real space of the viewer, sculpture took on a new relationship to the spectator whose phenomenological experience of an object became crucial to its meaning. Viewers were encouraged to move around—and sometimes on, in, or through—the works, many of which cannot be fully understood without peripatetic examination. Over the years Serra has expanded his spatial and temporal approach to sculpture and has focused primarily on large-scale, site-specific works that create a dialogue with a particular architectural, urban, or landscape setting.

Snake, a work made for the inauguration of the Guggenheim Museum Bilbao, consists of three enormous, serpentine ribbons of hot-rolled steel that are permanently installed in the museum's “Fish” gallery. Although it weighs around 180 tons, the colossal work is experienced through its negative spaces. The two tilted, snaking passages, capture a rare sense of motion and instability. Snake preceded Serra's Torqued Ellipses, the artist's most recent rumination on the physicality of space and the nature of sculpture. Both Snake and the Torqued Ellipses seem to defy gravity and logic, making solid metal appear as malleable as felt. Shifting in unexpected ways as viewers walk in and around them, these sculptures create surprising experiences of space and balance, and provoke a dizzying sensation of steel and space in motion.