Nesebar, often transcribed as Nessebar and sometimes as Nesebur, is an ancient city and one of the major seaside resorts on the Bulgarian Black Sea Coast, located in Burgas Province. The settlement was known in Greek as Mesembria, sometimes mentioned as Mesambria or Melsembria, the latter meaning the city of Melsas. Nesebar has on several occasions found itself on the frontier of a threatened empire, and as such it is a town with a rich history. Due to the city's abundance of historic buildings, UNESCO came to include Nesebar in its list of World Heritage Sites in 1983.

Whether built during the Byzantine, Bulgarian, or Ottoman rule of the city, the churches of Nesebar represent the rich architectural heritage of the Eastern Orthodox world and illustrate the gradual development from Early Christian basilicas to medieval cross-domed churches.