 The Church of Christ Pantocrator ( Bulgarian : църква „ Христос Пантократор “ , tsarkva „ Hristos Pantokrator “ or църква „ Христос Вседържател “ , tsarkva „ Hristos Vsedarzhatel “ , Byzantine Greek : Ναός Χριστού Παντοκράτωρος ) is a medieval Eastern Orthodox church in the eastern Bulgarian town of Nesebar ( medieval Mesembria ) , on the Black Sea coast of Burgas Province . Part of the Ancient Nesebar UNESCO World Heritage Site , the Church of Christ Pantocrator was constructed in the 13th – 14th century and is best known for its lavish exterior decoration . The church , today an art gallery , survives largely intact and is among Bulgaria 's best preserved churches of the Middle Ages . 
