It is the Grand Mosques (or AlMasjid Alharam) that Surrounds Kaaba in Mecca (or Makkah) in Saudi Arabia.
the biggest and the largest mosque in the world is MASJID-UL-HARAM it means KAABA-TULL AH
Anqara, Turkeia
Updated AnswerAl-Masjid al-Ḥarām (المسجد الحرام) or "The Sacred Mosque") or the "Grand Mosque", is the largest mosque in the world.This mosque is Located in the city of Mecca (or Makkah) in the Kingdom of Saudi Arabia. It surrounds the Kaaba, the place which Muslims turn towards while offering daily prayers and is considered by Muslims as the holiest place on earth.The mosque can accommodate up to 4 million worshippers during the pilgrimage (or Hajj) period, the largest annual people gathering in the world.It is worthy to mention that The Faisal Mosque in Islamabad is the largest mosque in Pakistan and South Asia and the sixth largest mosque in the world. It was the largest mosque in the world from 1986 to 1993. Faisal Mosque has the third largest capacity of accommodating worshippers in its adjoining grounds after the Masjid al-Haram (Grand Mosque) of Mecca, the Al-Masjid al-Nabawi (Prophet's Mosque) in Medina.
Covering an area of 5,000 square meters the mosque has the capacity to accommodate 300,000 worshippers, therefore, capicity-wise it is the largest mosque in the world.
Badshahi mosque is the second largest mosque in pakistan
Al-Masjid al-Ḥarām ("The Sacred Mosque"), in Mecca, Saudi Arabia is the largest mosque in the world. The second largest mosque in the world is the Prophet's Mosque also found in Saudi Arabia in Medina, and the third largest mosque in the world is Goharshad mosque which is in the city of Mashhad, Iran. http://en.wikipedia.org/wiki/List_of_largest_Mosques
Faisal Mosque in Islamabad Is the Largest Mosque of Pskistan. It is the 6th largest mosque of the world.It was the largest Mosque of the world from 1986 to 1993. it holds 15,000 people in it and 85,000 in it's courtyard.It is spread over 1,89,705 sq meters with 88 meters high minarets and 40 meter high main prayer hall.
The Badshahi Mosque is located at Iqbal Park, Lahore, Pakistan. The approximate location of the mosque is 31.588089' N, 74.310133' E. It was the largest mosque in the world from 1673 to 1986.
The lagest mosque in nigeria is kwara state mosque
Imam Reza Shrine in Iran, in terms of capacity.
The largest mosque in Norway is Central Jama'at-e Ahl-e sunnat.
the Great Mosque, Samarra