Boulogne-sur-Mer is a coastal city located in northern France, along the English Channel. It is known for its rich maritime history and serves as an important fishing port. The city features a mix of historical architecture, including the impressive Boulogne Cathedral and the medieval Château de Boulogne. The city is also famous for its beautiful beaches and the nearby Nausicaá, one of the largest aquariums in Europe. Boulogne-sur-Mer attracts tourists with its vibrant markets, delicious seafood, and scenic coastal views, making it a popular destination for both locals and visitors.