It's an unassuming 11th- and 13th-century building surrounded by lush vegetation, but UNESCO-listed Boyana Church evokes awe in art historians who struggle to explain how the three-dimensional facial expressions in the frescoes covering the interior came to be painted during the 13th century, since this innovation was ushered in by Italian Renaissance painters over a century later. It's a tourist-friendly spot. Upon payment you are provided with an English-speaking guide who will point out the emotive profiles and movements, and the introduction of realism into the choice of latter-day fashion and fabrics. The guide also will identify the models, including Kalogen and his wife, Desislava, the Sofia landlord and patron who commissioned the building of the 13th-century extension. With any luck you'll be the only ones in the church, as tour groups make for a claustrophobic experience. The church has not functioned as such since 1954.