Buenos Aires has also become a prominent center of contemporary street art; its welcoming attitude has made it one of the world's top capitals of such expression. The city's turbulent modern political history has "bred an intense sense of expression in ''porteños''," and urban art has been used to depict these stories and as a means of protest. However, not all of its street art concerns politics, it is also used as a symbol of democracy and freedom of expression. Murals and graffiti are so common that they are considered "an everyday occurrence," and have become part of the urban landscape of ''barrios'' such as Palermo, Villa Urquiza, Coghlan and San Telmo. This has to do with the legality of such activities —provided that the building owner has consented—, and the receptiveness of local authorities, who even subsidize various works. The abundance of places for urban artists to create their work, and the relatively lax rules for street art, have attracted international artists such as Blu, Jef Aérosol, Aryz, ROA, and Ron English. Guided tours to see murals and graffiti around the city have been growing steadily.