The Basilica of San Vitale in Ravenna, Italy, is one of the most important examples of early Christian Byzantine art and architecture in Europe. It is particularly well-known for the range of artful mosaics lining its walls and floor. The apse mosaic pictured here shows a beardless Christ in the middle flanked by two arch angels to his left and right hand side. The trio in the middle is surrounded by St Vitalis in the left corner and Bishop Ecclesius of Ravenna in the right corner.
Apse mosaic in basilica of San Vitale, Ravenna, Italy; colour photograph, 2015, photographer: Petar Milošević; source: Wikimedia Commons, Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).