Introduction to Boyana Cathedral: Boyana Cathedral (Boyana Church) is located on the outskirts of Sofia and was included in the World Cultural Heritage List by UNESCO in 1979. The oldest part of the church is the East Church, located on the east side. It was built from the end of the 10th century to the beginning of the 11th century. It is a single-arch chapel with built-in cross supports. The murals found in the church are very precious, using superb painting skills, and complexly and truly expressing the outstanding achievements of medieval Bulgarian culture.