Los Angeles–based artist Cliff Garten has just completed his latest commission: Ribbons, a series of landscapes and sculptures in the courtyard of the Beaux-Arts 50 United Nations Plaza in San Francisco. The symmetrical design riffs on the existing structure’s classical uniformity by inserting a sculptural collage of paving, seating, fountains, and plantings into the building’s 20,000 square foot courtyard.

Curving concrete pavers are set into a larger surface of decomposed granite, while cast concrete benches twist as if made of rubber, appearing to lift out of the ground pattern.

“Concrete is great. I think I have finally found my medium for infrastructure,” said Garten, who noted that he’s hoping to develop a line of street furniture with the manufacturer Quick Crete.

The project was commissioned by the General Services Administration’s Art in Architecture Program, which sets aside a half percent of construction funds for federal projects for art. See more pictures below.