Sveti Sedmochislenitsi Church, Sofia

The Sveti Sedmochislenitsi Church, formerly known as The Black Mosque, is an Orthodox church located in Sofia. It underwent a transformation from an Ottoman mosque to its current state between 1901 and 1902, officially opening on July 27, 1903. This church is dedicated to Cyril and Methodius and their five disciples, collectively known as the Sedmochislenitsi in the Orthodox Church.

The Black Mosque, built in 1528 by Suleiman the Magnificent, aimed to rival Christian churches in beauty. Its architect is uncertain but attributed to Mimar Sinan. It stands on the site of a former nunnery, Early Christian temple, and Roman temple dedicated to Asclepius discovered in 1901.

Originally named Koca Mehmed Pasha Mosque, it later became known as the İmaret Mosque due to its proximity to a discovered imaret in 1912. It had a square shape with a lead-covered dome and was located near a converted madrasah, a caravanserai, and a hammam. The minaret was made of dark granite, earning it the name the Black Mosque, but it collapsed in a 19th-century earthquake. After Bulgaria's independence in 1878, it served as a military warehouse and prison.

Russian architect Alexander Pomerantsev proposed converting the former Ottoman mosque into a Christian church. Bulgarian architects Milanov and Momchilov designed the dome, narthex, and bell tower in a Bulgarian style with Romantic influences. Construction began on May 27, 1901, and finished on May 6, 1902. Interior decoration was completed in 1996, with contributions from Tsar Ferdinand and Ivan Evstratiev Geshov. Prominent statesman Petko Karavelov was buried nearby in January 1903, supporting the church's construction.

Large candlesticks from 1903, made from old police badges of Eastern Rumelia and Bulgaria, stand in front of the altar. An electric clock, crafted by renowned watchmaker Georgi Hadzhinikolov in the 1930s, still functions on the western façade. The small garden and square nearby were also created during this time.