As of 2010, statistics show that approximately 1.5 billion people practice the Muslim faith, and this makes it virtually impossible to calculate the number of mosques. Mosques are being built in Canada, France and other places. Therefore, it’s hard to determine just how many mosques are currently being used.
Research shows that 22 percent of the population practices the Muslim faith. The number of Islamics are second only to Christians in population statistics, thereby making Muslim the second largest religion worldwide. Islam has grown about 3 percent annually, faster than the world’s population as a whole.
Most mosques in the Western world are located in London. Estimates to the number vary. The first London mosque was located in Notting Hill Gate, at 111 Campden Hill Road. Londoners state it was established in 1886 and was active during Edwardian times until 1930. Wikipedia