International Meridian Conference

A diplomatic meeting held in 1884 in Washington, D.C., where representatives from 25 nations convened to establish a standard prime meridian for global navigation and timekeeping.

The International Meridian Conference was a pivotal event in maritime history, addressing the need for a unified system of longitudinal reference to aid in navigation and time standardisation. Prior to the conference, various nations used different prime meridians, such as those passing through Paris, Greenwich, or other local observatories, leading to confusion and inefficiencies in global navigation and charting. The conference, attended by delegates from 25 countries, ultimately selected the Greenwich Meridian as the universal prime meridian, located at the Royal Observatory in Greenwich, England. This decision was based on the widespread use of Greenwich in existing nautical charts and the fact that the majority of the world’s shipping already relied on it for navigation.

The adoption of the Greenwich Meridian as the global standard had profound implications for maritime operations. It established a single, universally recognised reference point for determining longitude, which is crucial for plotting courses and ensuring safe passage at sea. Additionally, the conference laid the groundwork for the eventual adoption of Coordinated Universal Time (UTC), as it standardised the concept of time zones based on the prime meridian. This agreement significantly improved the efficiency and safety of international shipping and trade, fostering greater consistency in nautical practices worldwide. The decisions made at the International Meridian Conference continue to underpin modern maritime navigation and global timekeeping systems.