Agios Nikolaos tis Stegis is the only surviving katholicon (monastery church) of an 11th century Byzantine monastery in Cyprus. The church itself is dated to the 11th century, whilst the earliest written sources that mention the monastery are dated to the end of the 13th or the beginning of the 14th century. Apart from the church, no other monastic buildings survive today. The church is a domed cross-in-square structure and was originally without the narthex or the timber roof which covers both the nave and the narthex. This later steep-pitched roof, which carries a type of flat tile common in the area of Troodos, gave Agios Nikolaos the nickname 'of the Roof' ('tis Stegis') at least since the 13th century. The narthex was added at the beginning of the 12th century, whilst later additions and alterations changed the original appearance of the church and often resulted in the destruction of significant wall-paintings. The interior of the church is decorated with frescoes belonging to various periods, which cover a time span of over 600 years. (Source)