Late in the 19th century, Paris hosted two major international expositions: the 1889 Universal Exposition, was held to mark the centennial of the French Revolution and featured the new Eiffel Tower; and the 1900 Universal Exposition, which gave Paris the Pont Alexandre III, the Grand Palais, the Petit Palais and the first Paris Métro line. Paris became the laboratory of Naturalism (Émile Zola) and Symbolism (Charles Baudelaire and Paul Verlaine), and of Impressionism in art (Courbet, Manet, Monet, Renoir).