Since 1884 the meridian through the Royal Observatory in Greenwich has been considered the prime meridian for measuring longitudes around the world. However, there have been many other alternatives. Currently the Royal Mecca Clock Tower is being constructed in Saudi Arabia. One of the tower’s giant clocks was started for testing at the beginning of this year’s month of Ramadan.
Islamic scholars are indeed arguing that moving the prime meridian to Mecca would be historically more accurate and be used by a greater number of people. It’s unlikely that such a move would occur any time soon. But it does point out that the prime meridian is not a geographic location, like the equator or the poles. It is a reference point agreed to by convention.
Click here for articles on this subject that I have found.