The "salle des fêtes" of France's Élysée Palace is a place of power, pageantry and prestige. As well as press conferences and official dinners, it's here that the French president is sworn in. This ceremonial reception room has barely changed for more than a century and recently began to show signs of age. To give it a makeover, 150 French craftspeople were chosen for an exceptional job lasting two months. Tapestries, chandeliers, curtains and gilding: nothing was left to chance. We went behind the scenes.