Christo and Jeanne-Claude have collaborated on works of art since 1961. Their most recent work is The Gates, Central Park, New York City, 1979-2005 . Although The Gates remained in Central Park for only 16 days, the artists consider the twenty-six years of planning and applying for permits to be a part of the life of the project. The Gates used 5,290 tons of steel and 1,067,330 square feet of recyclable, rip-stop fabric. All the materials used in the 7,503 Gates were recycled.