Seat of the bishopric and home to a university, Reims is the biggest city in Picardy. Its cathedral is the largest religious structure in France. Compiègne is part of the department of the Oise. The castle where Napolean III and his wife often stayed during hunting trips in the surrounding forests is found in this city. It is worth taking a detour through Soissons, the ancient Merovingian capital.