Water, Water, Everywhere

The Venetian diarist, Marin Sanudo (1466-1536), summed up one of the paradoxes of Venice when he wrote: "Venexia è in aqua et non ha aqua" (Venice is in water and it doesn't have water). 
Fondaco dei Turchi (Natural History Museum), 11th century. One of the oldest surviving well-heads in Venice.
Given the location of the city, the sinking of wells was out of the question.
Well-head (vera da pozzo), Ca' d'Oro, Venice
And so the Venetians had to solve the problem of providing fresh water for its large population (in the 14th century Venice was the fourth largest city in Europe) by collecting rainwater. 
Early 15th century well-head (vera da pozzo), Corte Gregolina, Venice. A rare example of a basket-weave design.
The city's numerous campi and cortili were turned into extremely efficient water-storage facilities. The ground surrounding the well-head (vera da pozzo) sloped away so that the rainwater would flow though small stone drains (gatoli or pivelle) into large underground cisterns (up to 5 metres deep). There the water was sifted through sand to remove any impurities.
16th century bronze well-head (vera da pozzo), Palazzo Ducale, Venice
The well-heads in the campi were locked and the keys held by the local parish priests; it was the priest who decided when the well should be opened. This all changed in the 1880s with the advent of piped water from the mainland. The wells soon became surplus to requirement and thousands of well-heads disappeared. 
Vera da Pozzo, Corte S. Andrea, Venice
Many were sold off to foreigners, some were broken up, and some found other uses, often as rather elaborate plant pots. 
Well-head (vera da pozzo) Campo Santi Giovanni e Paolo, Venice
Taking many forms (round, square, hexagonal, octagonal, cylindrical), most well-heads, which date from the 9th to the 19th century, were carved out of Istrian stone, a few out of Verona marble and at least two were cast in bronze. Some are elaborately carved, others less so.  
Well-head (vera da pozzo), Campo de l'Abbazia, Venice
According to a census of 1858, there were 6046 private wells, 180 public wells and 556 disused wells in the city. Assuming that each well had a well-head, that cones to a grand total of 6,782. I wonder how many there are today. Alberto Rizzi in his fascinating and fact-filled volume, The Well-Heads of Venice, comes up with a figure of 2,500. 
Well-head (vera da pozzo), Hotel Stern, Venice
We all have our favourite well-heads and one of mine sits in the garden of the Hotel Stern. It is over a thousand years old (the well-head, that is, not the hotel!).