One's first introduction to it should be to ride the vaporetto (a bus on water) from the train station to Piazza San Marco, when one is overwhelmed with one wonder after another, until finally the horizon opens up, and one will never forget the moment of first seeing the lagoon and the Piazza and all the splendid buildings on farflung islands across the sparkling water, and Oh! and Ah!
The Piazza floods at high tide. One can sit on the steps of the amazingly beautiful Basilica San Marco and watch the water welling up through the interstices of the pavement, and who, seeing this for the first time, could not be profoundly moved and think deep thoughts of impermanence?
But then when you've seen it flooded a few times you notice how quickly they get the sawhorses out and the walkways up, and the tourists enjoy their special experience and life goes on.
One day I was there when it had snowed, the first snow in seven years, and the gleeful children took the sawhorses upside down and pushed each other joyfully along the white lines made by the marble set into patterns on the pavement of the Piazza. Beauty created centuries ago, sawhorses that emblemize the beauty's impermanence, combined in childish impertinence -- and isn't that a profound statement in its own right?
In Piazza San Marco Chess, the sixteen squares at the center of the board represent the Piazza. When the Piazza is dry, movement in the Piazza is normal, just like the rest of the board.
When the Piazza is dry, before each move a pair of standard dice is thrown, and if the total shown is three or less the Piazza will flood (a total of twelve is also special, as described later). The flooding takes place after each player has made one move.
When the piazza first floods, each player in turn constructs one walkway and specifies the direction of motion on that walkway. A walkway is a straight line of squares, that runs in one of the directions a Rook may move, connects two edges of the Piazza, and is one-way: motion occurs only in one direction, right, left, up, or down.
Walkways may not cross, so the first player to place a walkway makes a choice of vertical or horizontal that the opponent must also follow.
Pieces in the flooded Piazza may not move unless they are on a walkway; they do not drown, the water is not that deep, but they may not move. They are also safe from capture because no piece may enter a flooded square.
Pieces on a walkway may move one square in the direction of the walkway (they may not cross from one walkway to another), and may capture enemy pieces in so doing. They may not make their normal move. Just as an example of what a walkway can do, I'll mention that Pawns can take advantage of a walkway to move sideways, or Bishops can use a walkway to change colors.
Pieces may enter a walkway by making a normal move that ends on a walkway square, but may not cross over flooded squares to do so; a running piece, such as a Rook, Bishop, or Queen, must end its move when it first steps on a walkway -- can't keep running along it, nor across to the next walkway.
Pieces may leave a walkway only by making a walkway move.
The Piazza remains flooded for five turns (each player makes 5 moves), and then dries up. The walkways disappear and all is normal.
When the dice come up boxcars (two sixes, for a total of twelve), the Piazza is covered with snow. Any piece that both begins its move in the Piazza and also ends its move in the Piazza may move, but not capture, like a Rook; this is in addition to its normal move.
If a move either begins or ends in a non-Piazza square, the snow has no effect on it.
The snow melts after 5 turns and the Piazza is dry once more.
Venice is also a place where many tourists come from many different countries, and so it is appropriate to play Piazza San Marco Chess using different armies. However, you may notice that what I have described is really the Piazza San Marco board, and any variant of Chess or Shatranj or Shogi or Xiang Qi can be played on this board with equal fun.
Xiang Qi Elephants can use the walkways to fulfil their lifelong dream of crossing the river. No drops onto walkways.
There are no gondolas in this game.