The moat of the Tower of London is full of ceramic poppies.  Each poppy represents a British soldier killed in the First World War.  This 'installation' has grown over the summer and many thousands of people have visited it.  There are now 888,246 poppies.  After 11 November, the poppies will be removed.  Some will go on a tour of the UK.  The rest are being sold to raise money for charity.