Hagia Sophia: The Initial Meridian of the Ottomans

Today, the suburb Greenwich, in London is used as the First Meridian when determining geographical location and time. It has been recently discovered that during the Ottoman empire however the Hagia Sophia Mosque was accepted and used as the First Meridian.

Hagia Sophia: The Initial Meridian of the Ottomans


Today, the suburb Greenwich, in London is used as the First Meridian when determining geographical  location and time. It has been recently discovered that during the Ottoman empire however the Hagia Sophia Mosque was  accepted and used as the First Meridian.

An article published in the July edition of the Seven Continent and Cultural journal claims that the peak of the Hagia Sophia mosque was used as the First Meridian. Astronomer Puppy Emre, in his article titled “Ottoman First Meridian was Hagia Sophia” imparts important facts surrounding the use of First Meridian in history.

IN order to determine the geographical location on the First Meridian, the world uses “0”  as the accepted longitude – Emre states in the article “ The First Meridian is used as the measure for international time systems. A complete rotation around the world takes 24 hours and hence there are 24 divided time zones. It covers a 360 degree arc that spins on its axis and so it passes 15 different meridians”



The First Meridian were on the Canary Islands.

Astronomer Yakup Emre, his article continues on to say: “ In the First Age, Ptolemy in his map of the First Meridian, marked the Canadian Islands as the First Meridian. In the 6th Century some maps indicated this point as Baghdad or as Alexandria  and some as the Cape Verde Islands. During the 17th Century the meridian was initially considered to be Ferro Islands and used as the starting point. However, it was incredibly difficult to use an island in the middle of the ocean to determine longitude location. For this reason many countries, for convenience used their own capital cities as the initial meridian location. For France this was Paris, for Germany this was Berlin. The English used the London town of Greenwich.

Ulug Bey an Islamic scholar and the founder of the Semerkand Observatory who prepared the Zic-i (a ruler that had the coordinates of the celestial bodies), had noted that the Kamcatka eastern point was the beginning of the meridian. Kamcatka is at the most eastern point of Russia, north of Japan and is the most eastern point of earth. According to Greenwich mean time, it is the first point of sunrise.

Mustafa Ibn-Ali al-Muvakkit an Ottoman astronomer and timekeeper had also said that the starting point of the longitude was ten degrees east of the Canary Islands shore. In the 1560's,  at the Istanbul Yavuz Sultan Selim Mosque, Mustafa Ibn-Ali was the timekeeper and he passed away in 1571. In modern maps, the Canary Islands, which are a part of Spain are located in the Atlantic Ocean, west of Morocco.


The Ottoman Empire provided limited support to Greenwich

In 1884, 41 delegates from 25 countries came together with representatives from the Ottoman Empire at the conference “International Meridian Conference”  in Washington to determine the time zones for the world. At this conference, Greenwich, was accepted as the beginning meridian with 22 votes. The abbreviation GMT, Greenwich Mean Time, came to be accepted as the main form of time measure and was adopted internationally.  The Ottoman representative Ahmet Rustem Effendi used his vote for GMT  as “siding to use it as a common clock limited to international relations”.


The Royal Observatory in England which was set up in 1675 by King Charles II was set up at Greenwich and used for many years by sailors and cartographers alike. During the conference, instead of using cities such as Washington, Berlin and Paris it was agreed to use London’s Greenwich – one of the most important reasons being that more than 70 per cent of the sailors engaging in world trade used Greenwich as the main form of time measure.




Ottoman Acceptance of Hagia Sophia as the Main Centre

After the Washington conference, Ottoman cartographers used Greenwich on their maps as the base for time zone. However, on Ottoman lands the meridian that passes over the dome of Hagia Sophia mosque and the “Arz-Khalife” or the “Arz-i Istanbul” was continued to be use as the meridian. Muslims would use this as their measure for time. This practice ended with the introduction of the Calendar, Time and Measure Change law of 1932, and was replaced with GMT


Byzantine Zero Point was Sultanahmet Square


During the Byzantine era, the Million Pillar  was used as the beginning meridian. The Million Pillar  is currently  opposite the Hagia Sophia mosque north west of the Sultanahmet square. It is near the Basilica Cistern.  This monument erected in Constantinople was the starting place of measurement  of all old Roman roads  that lead to the cities of the Byzantine Empire and served the same purpose of the Millarium Aureum of Rome. It is believed that the this was built by Emperor Constantine 1 the Great and placed there in the 4th century.


Güncelleme Tarihi: 06 Aralık 2014, 14:38