Round Church, Preslav

The Round Church, also known as the Golden Church or the Church of St John, is a large partially preserved early medieval Eastern Orthodox church. It lies in Preslav, the former capital of the First Bulgarian Empire, today a town in northeastern Bulgaria. The church dates to the early 10th century, the time of Tsar Simeon I's rule, and was unearthed and first archaeologically examined in 1927–1928.

Considered to be one of the most impressive examples of medieval Bulgarian architecture, the Round Church takes its name from the distinctive shape of one of its three sections, the cella, which is a rotunda that serves as a place of liturgy. The church's design also includes a wide atrium and a rectangular entrance area, or narthex, marked by two circular turrets.

Source: Wikipedia