East wall of the Baptistère Saint-Jean in Poitiers, with Romanesque frescoes of the 11th and 12th centuries. The baptistery was built around 360, making it the oldest church in France. The east apse was added in the 6th or 7th century. Some of the frescoes date from the 11th century, including Constantine on horseback. Frescoes of the life of St. John the Baptist were painted over them in the 13th century.