The Quarter Mile Arc installation stretched in a gentle curve along the sand at the seaside town of Laguna Beach.
Clad in polished stainless steel, the thin posts were embedded into the beach so they stood vertically in a line.
Each measured almost twice the height of an average adult, and were spaced evenly to create a partial barrier between the town and the sea.
Smith used the slithers of reflective surfaces to mirror the landscape, as well as the soft light and dramatic sunsets that Southern California is famous for.
"Stretching along much of Main Beach, the arc forms a visible marker between the man-made and natural worlds, and reflects the changing colours of the ocean, sky, and shoreline throughout the day and night," said the artist.
From certain angles, the posts lined up so viewers could witness a full wall of reflection.
Seen from above, the shadows cast onto the sand created shifting patterns like sundials.
"Viewers may experience 1/4 Mile Arc both from a distance, with vantage points all along the cliffs and street, and from close up on the beach," Smith said.
Quarter Mile Arc was installed from 4 to 6 November 2016, as part of the Laguna Art Museum's Art and Nature programme.
Born in Los Angeles in 1972, Smith explores perceptions of light, colour and space in his work.
Previous examples of his installations include a shack clad in reflective bands to partially reflect the arid landscape of Joshua Tree, and a set of shiny cuboids at Coachella festival that transformed from mirrors by day to glowing neon beacons by night.
Photography and video are by Lance Gerber.