Spend your sixth day exploring Metz's modern architectural gems. Start with a visit to the Metz Métropole Pompidou Center, a contemporary art museum housed in a futuristic building. Admire the unique design and explore the thought-provoking exhibitions. Next, head to the Les Arènes de Metz, a modern concert hall known for its striking architecture. If you're interested in architecture, consider taking a guided tour to learn more about the city's modern architectural landmarks.