Seven Saints Church, Sofia

The Sveti Sedmochislenitsi Church, formerly known as The Black Mosque, is a Bulgarian Orthodox church located in Sofia. It was established between 1901 and 1902 by converting an Ottoman mosque and was officially inaugurated on July 27, 1903. This church is dedicated to Cyril and Methodius and their five disciples, collectively referred to as the Sedmochislenitsi in the Orthodox Church.

The Black Mosque, constructed in 1528 under the order of Suleiman the Magnificent, aimed to outshine the Christian churches in the city in terms of grandeur and beauty. Although commonly attributed to the renowned Ottoman architect Mimar Sinan, there is some uncertainty regarding its actual designer.

The mosque, measuring 25 meters in length, had a square layout with a large lead-covered dome. Adjacent to the modern church and the Count Ignatiev School, there now exists a small garden where a madrasah (a Muslim religious school) used to be situated. Following Bulgaria's liberation, this madrasah was repurposed as a prison. Nearby Ottoman structures included a caravanserai and a hammam.

Russian architect Alexander Pomerantsev suggested converting the old Ottoman mosque into a Christian church. Bulgarian architects Milanov and Momchilov designed the dome, narthex, and bell tower in a Bulgarian Romantic style. The central hall and dome were retained, while four oval bays, a narthex, and an altar section were added during a year-long construction phase. Interior decoration was finished in 1996.

The mosque earned its colloquial name, the Black Mosque, due to the dark granite used in the construction of its minaret. The minaret collapsed during a 19th-century earthquake, leading the Ottomans to abandon the mosque. After Bulgaria's liberation in 1878, the building was repurposed as a military warehouse and prison.