The Regia Hall in the Apostolic palace at the Vatican (2020). (Palais Apostolique - sala Regia - salle royale)The Regia hall was begun under Pope Paul III by Antonio da Sangallo the Younger and was completed in 1573. The elegant barrel vault is graced by the very impressive plaster decorations of Perino del Vaga. The stucco ornaments over the doors are by Daniele da Volterra. The walls were decorated by Livio Agresti; Giorgio Vasari and Taddeo Zuccari. The door in the center leads to the Cappella Paolina. (Paolina Chapel; chapelle Paolina / Pauline)-The grandiose and solemn Apostolic Palace is a secretive place; forbidden to the public and jealously guarded by the Swiss Guard. It hosts the Holy See administration; the Church's spiritual authorities and before all; the apartments of the Pontiff Sovereign.