A wall divides Canvey Island from the London River as a wall divides Florence from the Arno.
Both were ruptured within memory by flood waters, Canvey sea wall on
the night of January the 31st 1953 and the Arno walls on the night of
the 4th of November 1966. The floods wholly changed both places physically, socially, politically and culturally.
http://www.giorgiolotti.it/fotogiornalismo/AlluvioneFirenze.html