The Prophets Mosque in Medina is one of the biggest mosques in the world, the site of the tomb of Prophet Muhammad, and Islams second-holiest site.
The mosque and its surrounding areas have been extended many times to accommodate more worshippers. It was expanded by 40,440 square metres (sq m) in the mid-1970s and again a decade later.
Work on that expansion included the addition of 27 courtyards and escalators, and continued until 1992. Once completed, it took the mosques total area to 157,935 sq m.
A 2006 expansion, carried out by Saudi Binladin Group (SBG), extended the eastern courtyard by 35,000 sq m and added two car parks and more than 180 sunshades. The $1.25bn expansion was completed in 2011 and allowed for an additional 270,000 worshippers.
Another expansion scheme was started in 2012 that and aimed to take the mosques capacity to 2.6 million worshippers. SBG won the $1.5bn main contract and Lebanons Dar al-Handasah was appointed as the consultant.
However, work was halted in December 2015 by the Ministry of Finance. The decision was linked to the kingdoms efforts to cut spending following the oil price collapse. The project remains on hold.