The Palais du Luxembourg is where the French Senate meets, located in Paris. Originally built for Marie de Médicis, by Salomon de Brosse, the decoration was in charge of the artists Nicolas Poussin and Philippe de Champaigne. This palace was the residence of Napoleon Bonaparte, served as headquarters of the Luftwaffe in France during the German occupation of Paris, and you can visit this 17th century building for free, but you need to make a reservation before.