Vicaria, often known as Il Vasto, is one of the 30 quartieri of Naples, southern Italy, lying immediately to the east of the historical city centre. It borders the districts of Poggioreale, Zona Industriale and San Lorenzo, which together with Vicaria make up the 4th municipality of the city. It also borders the district of San Carlo all'Arena, in the 3rd municipality. Vicaria comprises a relatively small area, 0.72 km2. It had a population in 2009 of 16,369 inhabitants.