The fountains had very little water trickling through which spoiled the possibly beautiful effect. The 'artists' are mostly pedlars of mass produced art, none actually painting in the piazza, other than a couple of artists who used spray cans and various tools to produce gaudy pictures of nothing to do with Rome as far as I could see. There were 3 or 4 people, sprayed in either gold or silver who stood or sat very still until you approached and then they beckoned, hoping for payment. There were also a couple of girls with their heads buried inside their jackets, a pair of sunglasses and a hat up on a wire stalk that made them look like headless people. And of course, the eateries that encircle the piazza are grossly over-priced. Sorry, but it's not all it's cracked up to be.
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