I have mixed feelings about street art, generally – it damages property but it is also art and can sometimes send an important message.
I became fascinated with the street art I noticed in Italy (which is where the word graffiti originated). Graffiti comes from the word “graffio,” which literally means “a scratch” and which, according to Wikipedia, initially referred to “the inscriptions, figure drawings, and such, found on the walls of ancient sepulchres or ruins.”
Florence, the home of so much important art history, has some fascinating street art, as does Venice. You can see some examples in the pictures below and in the following articles: