Qom (also spelled "Ghom", "Ghum", or "Qum") (قم ɢom) is a city in the Central District of Qom County, Qom province, Iran, and serves as capital of the province, county, and district. It is the seventh largest metropolis and also the seventh largest city in Iran. The city is to the south of Tehran, and on the banks of the Qom River. At the 2006 census, its population was 957,496 in 241,827 households. The following census in 2011 counted 1,074,036 people in 299,752 households. The latest census in 2016 showed a population of 1,201,158 people in 356,976 households. Qom is considered holy in Shi'a Islam, as it is the site of the shrine of Fatimah bint Musa, sister of Imam Ali ibn Musa Rida (Persian: Imam Reza; 789–816). The city is the largest center for Shi'a scholarship in the world, and is a significant destination of pilgrimage, with around twenty million pilgrims visiting the city every year, the majority being Iranians but also other Shi'a Muslims from all around the world. Qom is also famous for a Persian brittle toffee known as sohan (Persian: سوهان), considered a souvenir of the city and sold by 2,000 to 2,500 "sohan" shops. Qom has developed into a lively industrial center owing in part to its proximity to Tehran. It is a regional center for the distribution of petroleum and petroleum products, and a natural gas pipeline from Bandar Anzali and Tehran and a crude oil pipeline from Tehran run through Qom to the Abadan refinery on the Persian Gulf. Qom gained additional prosperity when oil was discovered at Sarajeh near the city in 1956 and a large refinery was built between Qom and Tehran. Qom, the capital of Qom province, is located 125 kilometers south of Tehran, on a low plain. The shrine of Fatimeh Masumeh, the sister of Imam Reza, is located in this city, which is considered by Shiʿa Muslims holy. The city is located in the boundary of the central desert of Iran (Kavir-e Markazi). At the 2011 census its population was 1,074,036, comprising 545,704 males and 528,332 females. Qom is a focal center of the Shiʿah.