Saint George Rotunda

Dating back to the early 4th century (approximately 330 AD), this early Christian red brick rotunda is considered the oldest preserved building in the city. It is part of an ancient archaeological complex and has historically served various purposes, including as a baptistery, a mausoleum, and a museum.

The interior is noted for its medieval frescoes, with notable layers dating from the 12th to the 14th centuries. During the Ottoman period, the building was converted into a mosque and the frescoes were covered, though they were later revealed and restored in the 20th century.

The structure is a cylindrical domed building set on a square base, representing a unique example of early Christian architecture. It currently remains an active Bulgarian Orthodox place of worship and is protected as a national monument.