"Did you ever happen to see a city resembling this one?" Kublai asked Marco Polo, extending his beringed hand from beneath the silken canopy of the imperial barge, to point to the bridges arching over the canals, the princely palaces whose marble doorsteps were immersed in the water, the bustle of light craft zigzagging, driven by long oars, the boats unloading baskets of vegetables at the market squares, the balconies, platforms, domes, campaniles, island gardens glowing green in the lagoon's grayness.

The emperor, accompanied by his foreign dignitary, was visiting Kin-sai, ancient capital of deposed dynasties, the latest pearl set in the Great Khan's crown.

"No, sire," Marco answered, "I should never have imagined a city like this could exist."

The emperor tried to peer into his eyes. The foreigner lowered his gaze. Kublai remained silent the whole day.

After sunset, on the terraces of the palace, Marco Polo expounded to the sovereign the results of his missions. As a rule, the Great Khan concluded his day savoring these tales with half-closed eyes until his first yawn was the signal for the suite of pages to light the flames that guided the monarch to the Pavilion of the August Slumber. But this time Kublai seemed unwilling to give in to weariness. "Tell me another city," he insisted.

". . . You leave there and ride for three days between the northeast and east-by-northeast winds . . . " Marco resumed saying, enumerating names and customs and wares of a great number of lands. His repertory could be called inexhaustible, but now he was the one who had to give in. Dawn had broken when he said: "Sire, now I have told you about all the cities I know."

"There is still one of which you never speak."

Marco Polo bowed his head.

"Venice," the Khan said.

Marco smiled. "What else do you believe I have been talking to you about?"

The emperor did not turn a hair. "And yet I have never heard you mention that name."

And Polo said: "Every time I describe a city I am saying something about Venice."

"When I ask you about other cities, I want to hear about them. And about Venice, when I ask you about Venice."

"To distinguish the other cities' qualities, I must speak of a first city that remains implicit. For me it is Venice."

"You should then begin each tale of your travels from the departure, describing Venice as it is, all of it, not omitting anything you remember of it. "

The lake's surface was barely wrinkled, the copper reflection of the ancient palace of the Sung was shattered into sparkling glints like floating leaves.

"Memory's images, once they are fixed in words, are erased," Polo said. "Perhaps I am afraid of losing Venice all at once, if I speak of it. Or perhaps, speaking of other cities, I have already lost it, little by little."

Italo Calvino, Le Città invisibili, Einaudi, Torino, 1972 [Prologue to Chapter 6]

If you want to read more, you can get pdf files of the original by Italo Calvino and the English translation by William Weaver.