Al-Muwahideen Mosque in Algeria was built around 1940 by Sheikh Sidi Mohammed Ben Bhos, a popular sufi scholar. The mosque was built underground to remain hidden from French authorities, who had been suppressing open practice of Islam. Over the coming years the mosque became a hotspot for scholars and students from across the country, and soon became a centre for the resistance movement. In 1950, the French caught wind of the Mosque’s activities and shut it down, exiling it’s founder. However, the seeds had been sown and twelve years later Algeria gained it’s independence. To this day, locals continue to perform salah underground, particularly during times such as Ramadan.

The mosque was built underground, with an area of ​​200 square meters and a depth of 6 meters. The entrance to the mosque is a small gate located above the ground, from which worshippers descend on elaborate stairs that were completed during the excavation operations.