Originally built as a mosque in the 15th century and nicknamed the Black Mosque because of the dark granite of its exterior, this building once stood in the center of a vibrant Muslim quarter.
A 19th Century earthquake and the decline of the Ottoman Empire left the mosque in poor condition and it was soon deserted.
Briefly used as a prison after Bulgaria's independence, the building was soon redesigned into an Orthodox church.
The church is named after the much revered St. Cyril and St. Methodius. (the brothers who created the Cyrillic alphabet) and their five followers who brought the alphabet to Bulgarian lands, thus giving the total of seven saints or sedmochislenitsi.
The church also has a famous choir. Unfortunately, it only performs on special occasions.