The International Meridian Conference designates the Royal Observatory, Greenwich as the world's prime meridian.
The International Meridian Conference was a conference held in October 1884 in Washington, D.C., in the United States, to determine a prime meridian for international use. The conference was held at the request of U.S. president Chester A. Arthur. The subject to discuss was the choice of "a meridian to be employed as a common zero of longitude and standard of time reckoning throughout the world".
It resulted in the recommendation of the Greenwich Meridian as the international standard for zero degrees longitude.
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Sources and further reading: Wikipedia — International Meridian Conference, Royal Observatory, Greenwich (CC BY-SA). Images: Wikimedia Commons.
