Abraj Al Bait

The project uses clock faces for each side of the main hotel tower. The highest residential floor stands at 370 m (1,210 ft), just below the media displays under the clock faces. At 43 m × 43 m (141 ft × 141 ft), these are the largest in the world. The roof of the clocks is 450 m (1,480 ft) above the ground, making them the world's most elevated architectural clocks. A 151-metre-tall (495 ft) spire has been added on top of the clock giving it a total height of 601 m (1,972 ft). Behind the clock faces there is an astronomy exhibition. In the spire base and the glass-covered floors (The Jewel) there is a scientific center which is used to sight the moon in the beginnings of the Islamic months, and to operate an atomic clock which controls the tower clocks.[12]

A view of Clock Tower from Kaaba

The clocks are topped by a 128-metre (420 ft) spire with a 23-metre-high (75 ft) golden crescent at the top. The spire has an eight-story glass-covered base (The Jewel) which belongs to a scientific center having its own small exhibition, another observation deck at 475 m (1,558 ft) and a prayer floor in 480 m (1,570 ft). The highest floor in The Jewel is the Control Tower Floor, which was planned to be used for controlling air traffic in the sky above Mecca (mainly helicopters as airplanes are not allowed near Mecca). However, this was skipped for technical reasons and the future usage is not clear yet. Above from The Jewel the spire has only technical installations for sound, light and other infrastructure and eventually the last viewing deck and the crescent above it. The crescent has two regular floors with living areas and a few service floors and rooms.

The crescent was constructed in Dubai by Premier Composite Technologies in April 2011. The crescent is made of fibreglass-backed mosaic gold, and it weighs up to 35 tonnes. Peugeot Joseph, the company official, said a team of five engineers and a hundred workers carried out the project, which cost 90 million United Arab Emirates dirhams and took three months to build.

The company has also constructed the Mecca Clock. The crescent was divided into 10 parts to move it to Mecca.[20] The crescent was partly assembled on the base of the clock face to reduce it to 5 parts. Those five parts were then lifted and installed above the spire from 20 June to 6 July 2011.

The minaret and its base have loudspeakers which broadcast prayer calls to a distance of 7 km while nearly 21,000 lamps illuminate the surrounding area to a distance of 30 km (19 mi). During occasions like Muslim Eids and new Hijri years, a 16-beam light illuminates an area of a diameter of around 10 km (6 mi) while 21,000 lamps beam white and green lights to a distance of 30 km (19 mi). The light beams are intended to allow the deaf, and Muslims in more distant parts of Mecca and nearby cities, to know prayer timings.[21]

The Abraj-Al-Bait complex had two fire incidents during construction. The first fire accident was at Hajar Tower on 28 October 2008. It took 400 firefighters to put out the fire, which burned for 10 hours, consuming nine floors of the tower.[22] According to eyewitness reports, the blaze erupted shortly after midnight, and spread rapidly because of wood used for construction stored in the premises. Soon, the entire building was engulfed in smoke. Hospitals were put on high alert, but no injuries were reported. A civil defence spokesman said the fire started on the 32nd floor of the Hajar Tower.[23]

The second fire struck the Safa Tower on 1 May 2009. No deaths or injuries were reported in the blaze which was quickly contained by Civil Defence. Eyewitnesses said the fire broke out soon after Asr prayer while some workers in the building were welding iron rods on wooden scaffoldings. The fire damaged a large part of the under-construction tower. According to Major General Adel Zamzami, director general of Civil Defence in the Mecca province, the fire broke out at the 14th floor and reached up to the 20th.[22]

The construction engendered some controversy as the location chosen for the towers was the historic 18th-century Ottoman Ajyad Fortress, which was demolished to make way for them.[24] The development has been criticised by The Guardian for having "transformed a type of architecture that evolved from a dense urban grain of low-rise courtyards and narrow streets into ... an endlessly repeatable pattern for the decoration of standardised [concrete] slab(s)".[25]