The Bulgarian-born artist Christo is famous for a series of eye-catching works.
With his wife and artistic partner, Jeanne-Claude, he created The Gates in New York's Central Park.
He also famously wrapped Berlin's Reichstag in fabric;
This week he received permission from the US federal government for his next project: an artwork called "Over The River".
"Over The River"
Christo will place a series of billowing panels of translucent fabric along sections of the Arkansas River in Colorado.
There will be eight sections in all, between Salida and Canon City, along a 42 mile stretch of the river. In total, just under 6 miles will be covered with fabric.
At his studio in New York last year, he gave more details to PRI's The World:
"The fabric is only above the water, meaning that the width of the fabric varies with the width of the water. Sometimes [the panels are] 45 feet wide, sometimes they're 120 feet wide."
Christo says there will be two principal ways to experience the artwork, one from the highway running alongside the river, and the other from the river itself.
Christo's studio is at the very top of a town house in lower Manhattan. The walls are covered with sketches and drawings, for "Over The River" and other projects.
"I don't allow anyone to move anything," he says. "I have no time. I have no time to do anything but to work on my art."
Christo pays for his projects by selling some of the sketches, but the artwork itself will be transient. "Over The River" will exist for two weeks only, in the summer of 2014.
"Humans have this enormous pleasure to be in the presence of something once in a lifetime, never again."
And Christo is excited to see how the idea of "Over The River" will change as it goes from paper and pencil to rock and water.
"We do not know, myself and Jeanne-Claude, how the project will look."
Christo talks about Jeanne-Claude as if she were still working on "Over the River". The two conceived the idea almost twenty years ago. But she died in 2009.
"I always say 'we' because I can't think without her. You know, the most important things I miss about Jeanne-Claude was that she was extremely critical, very argumentative. This is the most empty place, and there's no way to substitute. No way."