„The Great Mosque of Mecca“, also known as the Haram Mosque, is a site of pilgrimage for the Hajj, and surrounds the Kaaba in the city of Mecca. Every Muslim must do the Hajj at least once in their lives if able, which includes circling the Kaaba seven times within the mosque. The Haram Mosque has undergone major renovations and expansions through the years under the control of various caliphs, sultans and kings.

In 2008, the King of Saudi Arabia, who is titled the Custodian of the Two Holy Mosques, started the planning of the expansion of “The Great Mosque of Mecca“. To serve the increasing amount of pilgrims, the mosque's capacity needs to be raised from 770,000 to over 2.5 million worshippers. In August 2011, the Government under King Salman started with the expansion, which covers an area of 400,000 m2 (4,300,000 sq ft). Now the Haram Mosque is the second largest building in the world and the largest mosque. Equipped with a huge sliding dome and sliding hatches, a four level walkway (Mataf) and two new minarets, bringing the total number of minarets to eleven, it´s an impressive piece of architecture and technology. All closed spaces are air conditioned. 

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The biggest clock in the world

To accommodate the worshippers, a new complex in the north of the Mosque has been built, including a multi-level stairways and tunnels, a gate named after King Abdullah, and a huge hotel arrangement crowned by a 601m high clock tower, the “Abraj Al-Bait“, (Arabic: Towers of the House). PCT built the Clock faces and clock hands, the composite ceiling above the clock and the crescent with prayer rooms. At 43 m × 43 m (141 ft × 141 ft), the four clock faces are the largest in the world, visible from 25 kilometres (16 miles) away. 

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PCT has built major parts for the expansion of the Haram Mosque:

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