That is the question that always comes to mind when I see and think of Venice, Italy. How in the world did they build this whole city on the water? Better yet, why? According to my internet research, it is apparently build over many small islands (you see no land there), and also upon petrified wood foundations, which makes them literally rise out of the water. As for the why, I am not sure. I am sure it had something to do with maritime transport of goods and such. If you would like to learn more, just google it. :) I have a few more travel pictures here from Venice that fascinate me continually, and I thought I'd share.
Here was a scene from the canal. You can see where people dock their boats, and a boat or two traveling in the canal. There are literally NO cars here.
The white boat you see in the water here is the "bus". It's the public transportation system here. I will admit, I had to ensure that I was ready to board it, as I do get seasick at times. You can see a crane in the background as they were doing some construction on the city. Don't ask me how. :)
The two above pictures are of St.Mark's Square. They are not the best, so I apologize for that. The top one shows the St. Mark's Basilica and Doge's Palace, which is just a fancy palace in which Doge (duke's of Venice) lived. The second just shows all the pigeons that reside there. I think that often if you see San Marco's square in movies, the pigeons are there as well.