Royal Observatory Greenwich began as a practical answer to a problem at sea: how to establish longitude. Its hilltop instruments and buildings connected astronomical observation with navigation, timekeeping, and the standard reference line later adopted for global maps.
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The Royal Observatory stands on a hill because the view of the sky mattered to its original purpose. King Charles II commissioned the observatory in 1675 to support the search for a reliable way to determine longitude, a pressing problem for navigation.
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- Charles II commissioned the observatory in 1675.
- John Flamsteed was the first Astronomer Royal.
- John Harrison’s marine chronometers were tested at Greenwich.
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