Qom lies 125 kilometres southwest of Tehran and is the capital of Qom Province. At the 2011 census its population was 1,074,036. It is situated on the banks of the Qom River. Qom city enjoys a dry and warm climate with low annual rainfall due to remoteness from the sea and being situated in the vicinity of desert.
Qom has developed into a lively industrial centre owing in part to its proximity to Tehran. It is a regional centre 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 is considered by Shia Muslims to be the second most sacred city in Iran after Mashhad, as it is the site of the shrine of Fatema Masume, sister of Imam `Ali ibn Musa Rida (Persian Imam Reza, 789–816 AD). In Shia Islam, women are often revered as saints if they are close relatives to one of the Twelver Imams. Fatima Masumeh is therefore honored as a saint, and her shrine in Qom is considered one of the most significant Shi'i shrines in Iran. Every year, thousands of Shi'i Muslims travel to Qom to honor Fatima Masumeh and ask her for blessings. The mosque consists of a burial chamber, three courtyards and three large prayer halls, totalling an area of 38,000 m2.
Another interesting place in Qom is a village called Jamkaran. Jamkaran is located on the outskirts of Qom, and is the site of the Jamkaran Mosque, a popular pilgrimage site for Shi'ite Muslims. Local belief has it that the Twelfth Imam (Muhammad al-Mahdi) — a messiah figure Shia believe will lead the world to an era of universal peace — once appeared and offered prayers at Jamkaran. On Tuesday evenings especially large crowds of tens of thousands gather at Jamkaran to pray and to drop a note to the Imam in a well at the site, asking for help with some problem.
The city is the largest center for Shi'a scholarship in the world, and is a significant destination of pilgrimage. Qom is well known for its many religious seminaries and institutes that offer advanced religious studies, which made this city the largest center for Shia scholarship in the world. There are an estimated 50,000 seminarians in the city coming from 80 countries, including 6,000 from Pakistan alone. Qom has seminaries for women and some non-Shia students. Most of the seminaries teach their students modern social sciences and Western thought as well as traditional religious studies.
Qom is famous for a brittle toffee called "sohan", considered a souvenir of the city and sold in numerous shops all around the city.