The Piazza San Marco is surrounded by buildings;
these structures, which range in both age and architectural style, provide the backdrop to a view that would otherwise just be a bunch of paving stones and some pigeons.
In between the Piazza and the Bacino Orseolo you'll find the three-storey "Procuratie Vecchie".
The original structure that stood here had two floors and was built in the twelfth century.
Today's version was completed in the sixteenth century after the original was damaged in a fire.
If you walk from the Piazza to Bacino Orseolo, you'll pass through one of these openings in the structure, the Procuratie Vecchie has five or six of them, they are like very small atriums.
Perhaps one of you has better knowledge of architectural terminology.
For now, I like to call them "windows to the sky".