<p>Cathedrals and great churches are among the most iconic sights of the world's towns and cities.<br><br>Visible from miles around, the cathedrals of Canterbury, St Paul's, Chartres and St Stephen's in Vienna dominate their skylines. Others surprise by their statistics: Salisbury has Britain's tallest spire, Wells the largest display of medieval sculptures in the world, while King's College Chapel in Cambridge boasts the largest fan vaulting in ...