The four-faced clock tower in the Holy City of Mecca

Muslims pray inside the Grand Mosque, with the Mecca Clock lit up in the background, on the first day of the fasting month
 of Ramadan in Mecca

This is what the four-faced clock tower in
 the Holy City of Mecca will look like when finished
. The clock, billed as the world's biggest with a
diameter of 40 meters (130 feet), will sit atop the second highest building in the world

The under construction four-faced clock, atop the Abraj Al-Bait Towers is seen overlooking  the Grand Mosque in Mecca in Mecca, Saudi Arabia