One of the coolest places I've ever visited. The LX Factory in Lisbon. It once was a manufacturing site but for over a decade has transformed into an artist's playground for every style. One of the coolest wall art pieces, if a bit startling for those of us who aren't fond of insects, is by Bordalo II. He's an incredible mixed media artist who's work can be seen in cities across the globe. Definitely worth a Google search if you're curious.