A nun takes pictures as believers mark 1,700 years since the Edict of Milan, when Roman emperor Constantine issued instructions to end the persecution of Christians, in the southern Serbian city of Nis October 6, 2013. Nis, some 220 km (137 miles) south of Belgrade, is the birthplace of Constantine the Great, the first Roman emperor to convert to Christianity. The Edict of Milan, which he had a part in enacting, proclaimed official tolerance of Christianity across the Empire. REUTERS/Marko Djurica (SERBIA - Tags: RELIGION SOCIETY ANNIVERSARY TPX IMAGES OF THE DAY)