Hagia Sophia is a very old church in Sofia and a very famous masterpiece of Byzantine architecture. The city of Sofia is also named after the Hagia Sophia. The church has a long history, the main nave and the two towers and one domed tower on the east side were all built in the middle of the 6th century. The floor inside the church has very intricate early Christian decorations or mosaics of flowers and animals, and there are tombs under and around the church that predate the construction of the church.