The title of the series is a playful merging of the words “petroglyphs” (carvings on stone) and “metro plots,” Ruscha’s own term for city maps. In the prints, Los Angeles streets wind through barren topographies like dry riverbeds. They are perhaps the artist’s visual meditations on the inevitable result of overdevelopment and the environmental degradation of the western landscape—post-apocalyptic visions in which the depopulated city has returned to its desert origins in a drought- stricken future.