Romanticism architecture emerged in the 18th and 19th centuries as a reaction to Neoclassical symmetry, emphasizing emotion, individualism, nature, and the past. It is characterized by asymmetrical and organic shapes, curved forms, and blending different architectural elements. Notable examples include Notre-Dame de Paris and Neuschwanstein Castle in Germany, known for its fairy-tale detailing. Prominent French architect Eugène Viollet-le-Duc contributed significantly to 19th century architecture through his philosophies on restoration, rationalism, Gothic revival, and emphasis on structural integrity.