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The Serpentine (also known as the Serpentine River) is a 28-acre (11 hectare) recreational lake in Hyde Park, London, created in 1730

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The artist Christo designed The London Mastaba, a 20-metre-high sculpture floating on London's Serpentine Lake, which represents his and late wife Jeanne-Claude's determination to make art free.
Based on the trapezoid shapes of mastaba, an Arabic word for bench given to Egyptian tombs and seats found outside homes in ancient Mesopotamia, the temporary sculpture is the realisation of the artistic duo's shared dream of creating a floating version of a form that has fascinated them for half a century.
The London Mastaba, which is made of 7,506 painted barrels secured to scaffolding and anchored in the lake, was entirely self funded and is free to view by all.