'The traveller approaching Venice … gazes out on the same flat, desolate expanse of water and reed and marsh that the first Venetians chose for their own; and is struck, more forcibly every time, not just by the improbability but by the sheer foolhardiness of their enterprise. It is a curious world, this world of the Venetian lagoon; some 200 square miles of salt water, much of it shallow enough for a man to wade through waist-deep, but criss-crossed with deeper channels along which Venetian shipping has for centuries made its way to the open sea; … And yet, especially on autumn evenings when the days are drawing in and the surface glistens like oil under a low, misty sun, it can be beautiful -so beautiful that one is surprised that the great Venetian painters, seduced as always by the splendour of their city, took so little interest in their less immediate surroundings. How differently the Dutch would have reacted! But then the Venetian school was essentially joyous; the lagoon, for all its beauty, can be quite unutterably sad.'

John Julius Norwich, A History of Venice, published by Penguin