For almost 50 years, the artist duo Christo and Jeanne-Claude have collaborated on temporary, grand-scale art installations all over the world. Christo just unveiled their latest work, The London Mastaba, a 7,506-barrel sculpture floating on the Serpentine lake in Hyde Park. Mastaba, which means “bench” in Arabic, is a severed pyramid shape first seen 6,000 years in Mesopotamia. Before this, the artists enveloped 11 Florida islands in hot pink fabric; hung thousands of saffron banners throughout Central Park in New York; and enabled people to walk on water with their Floating Piers in Italy. Though Jeanne-Claude passed away nine years ago, Christo continues to construct pieces the two had planned together. Originally conceived in 1977, The London Mastaba is actually a test run for a larger, permanent mastaba in the United Arab Emirates. If carried through to completion, The Mastaba would be the largest sculpture in the world, as well as the duo’s only permanent large-scale work.