Multiple layers of complicated history, destruction and repair of Urbnisi Cathedral are visible on its walls. The oldest fragments are easily recognized, as they are made of well-hewn sandstone blocks. Over the years it was repaired using a wide variety of stones.
The cathedral has three entrances and three floors. The oldest, original stones are only found at the southern entrance.
About 15 meters from the cathedral, on the western side, there is a bell tower made of crushed stone. An inscription in the ancient Georgian Asomtavruli script on its western façade tells us the bell tower was built in 1706, on the orders of Vakhtang VI.