Photo of Meridian at Greenwich. By international convention, the modern Prime Meridian passes through the Royal Observatory, Greenwich , in southeast London, United Kingdom, is known as the International Meridian or Greenwich Meridian.
<a href="//commons.wikimedia.org/wiki/User:Apletters" title="User:Apletters">Apletters</a>
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<span class="int-own-work" lang="en">Own work</span>