The Norman Palace, also known as the Royal Palace, is located in Palermo. The palace is the oldest royal residence in Europe, home to the kings of the Kingdom of Sicily, imperial seat with Frederick II and Conrad IV. On the first floor of the building stands the Palatine Chapel. Since 2015 it is part of the World Heritage Site (Unesco). Many works of art contained in the Palace, with nineteenth and twentieth century masterpieces by Francesco Lojacono, Antonino Leto, Joan Mirò and Renato Guttuso.