Anamorphosis is a distorted projection or perspective requiring the viewer to use special devices or occupy a specific vantage point to reconstitute the image.

Between 11 and 25 March 2007, Swiss artist Felice Varini and his team created an unusual piece of public art that is set to baffle and fascinate visitors to Cardiff Bay barrage. The piece, entitled 3 Ellipses for 3 Locks, was commissioned by arts agency CBAT for the Cardiff Harbour Authority and cost $50,000. A series of three yellow ellipses have been painted onto the working locks, gates and even the outer sea wall to create a piece that took a year to plan. All you have to do to see Felice Varini's 'anamorphic illusion' properly formed, is find a precise vantage point somewhere on the barrage.