Meridian Line & Historic Royal Observatory

Closure of Observatory Life

The Observatory Life gallery will be closed for essential maintenance 1-2 August. Other galleries at Flamsteed House, including the Octagon Room, remain open.

Suspension of Time Ball

The Time Ball is temporarily not in operation, due to damage from recent weather conditions.

The historic Royal Observatory is the home of Greenwich Mean Time (GMT). Enter the Meridian Courtyard to get your essential photo standing on the Meridian Line and explore some of the oldest parts of the site including the Astronomer Royal's house.
Explore & discover

Stand on the historic Prime Meridian of the World and see John Harrison's legendary timekeepers

Who designed the telescope that defined the Prime Meridian?

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So what is longitude anyway and what made it so hard to measure?

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Enjoy a lunch over looking Greenwich Park and pick up a memento of your visit

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