Makkah clock tower, the world's largest of its kind, is built adjacent to the Holy Grand Mosque in Makkah al-Mukarramah, which is the largest mosque on earth as well as the holiest spot on earth for all Muslims. The Clock Tower is a unique architectural monument which was designed with the assistance of the foremost engineering expertise and constructed by the most skilled artisans, who together have produced the wonder we see today. With a front diameter of more than 40 meters and a great height of more than 400 meters above the earth's surface, it is easily visible from anywhere in Makkah al-Mukarramah, as well as from the approach roads to the Holy City from all directions. The clock consists of four faces equipped with the size of the two front and rear faces amounting to 43X43 meters and the size of the side fronts reaching 43X39 meters. The four faces were also equipped with devices which emit laser beams on various occasions in addition to light signals at the time of the call to prayer. For protection against dust, wind and rain, the clock is equipped with a comprehensive system of protection from these elements. The length of the Arabic letter 'alif' in the phrase "Allah Akbar" (God is great) which can be seen above the watch is more than 23 meters and the diameter of the crescent is 23 meter making it the world's biggest man-made crescent. The electricity required to operate the Makkah al-Mukarramah Clock comes from solar panels, and it is connected to the Makkah al-Mukarramah electric power grid for extra power. The gross weight of the clock is 36,000 tons, constructed on an 14,000 pieces of iron chassis weighing nearly 12,000 tons. Some of the clock's heaviest parts weigh as big as nearly 15 tons. Around 250 highly-silled laborers were recruited to achieve the iron works of the clock, particularly to fix and install the highest parts of the clock tower as well as the iron chassis at a highet of 600 meters. This unique clock is covered with more than 98 million pieces of colored glass mosaics in addition to more than two million LED cells for illumination. In addition, the clock is covered with more than 43,000 square meters of advanced carbon fibers. Each hand of the clock is powered by an independent motor, both of which are contained in a single assemblage which weighs more than 21 tons, thereby making it the biggest and heaviest clock operating assemblage anywhere. The clock is powered by four operating units, one for each of its faces, and each face receives the same signal at the same time, in coordination with the most modern atomic system in the world. The crescent which crowns the tower is also considered to be the largest in the world, with a diameter of 23 meters. The length of the Arabic letter 'alif' in the phrase "Allah Akbar" (God is great) is more than 23 meters. The call to prayer resounds from the pinnacle of the Makkah al-Mukarramah Clock through the most powerful sound system of its kind, and during the call to prayer 21,000 green and white lights illuminate the clock, thereby increasing its visibility in all areas of Makkah al-Mukarramah.
