The Kuklen Monastery St Vrach (Healer) was one of the biggest cultural centers of Bulgaria in the Middle Ages. It was built during the Second Bulgarian State, upon the remains of an ancient Thracian sanctuary. The monastery was destroyed by the Turks in the 17th century, and after it was restored, it turned into a big literature school, where the hieromonks Sidor, Anani and Krustiu Gramatik created their works of art. The most significant among all the preserved documents, created here, is the Kuklen psalm-book Pesnivets, written in 1337 under the will of Tsar Ivan Alexander. Other ancient books, written in the monastery, are preserved today in the libraries in Plovdiv and Sofia. Two layers of frescoes were discovered in the church, the first layer is Bulgarian and dates back from the 17th century, and the second layer is Greek, dating back from the 19th century.