The Spinnaker Tower is a 170 m (558 ft)–high tower in Portsmouth. It is the centrepiece of the redevelopment of Portsmouth Harbour, which was supported by a National Lottery grant. Its shape was chosen by Portsmouth residents from a selection of concepts. The tower reflects Portsmouth's maritime history by being modelled after a sail. After several years of delays and cost overruns, it was opened on 18 October 2005.
My great aunt and uncle used to live in a flat on the ground floor of the block with the red mural on the side. Unfortunately their flat faced inland, so no views of the harbour. As far as I remember the murals were made of tiles and must have been quite controversial when the blocks were built.