Located within the Cité de Carcassonne, the Basilica of Saints Nazarius and Celsus is a beautiful example of Gothic and Romanesque architecture. The basilica features stunning stained glass windows, intricate stone carvings, and a serene interior. Visitors can explore the nave, admire the detailed sculptures, and experience the peaceful atmosphere. The Basilica is a significant religious site with a rich history, making it a must-visit for those interested in ecclesiastical architecture and heritage.