Henry Wadsworth Longfellow - Venice

White swan of cities, slumbering in thy nest
So wonderfully built among the reeds
Of the lagoon, that fences thee and feeds,
As sayeth thy old historian and thy guest!
White water-lily, cradled and caressed
By ocean streams, and from the silt and weeds
Lifting thy golden filaments and seeds,
Thy sun-illumined spires, thy crown and crest!
White phantom city, whose untrodden streets
Are rivers, and whose pavements are the shifting
Shadows of palaces and strips of sky;
I wait to see thee vanish like the fleets
Seen in mirage, or towers of cloud uplifting
In air their unsubstantial masonry.

Henry Wadsworth Longfellow

http://www.poemhunter.com/poem/venice-9/