The Greenwich Observatory, located in Greenwich, London, is a historic site known for its significant contributions to astronomy and navigation. Established in 1675, it was the first observatory to use the prime meridian as the reference point for measuring longitude. The observatory played a crucial role in the development of accurate timekeeping and the establishment of standard time zones. Today, the Royal Observatory Greenwich is part of the National Maritime Museum and attracts visitors interested in astronomy and maritime history. It features exhibits on celestial navigation, timekeeping, and the history of space exploration, making it a popular educational destination.