Cheomseongdae Astronomical Observation Tower, Royal Tombs burial mounds, UNESCO World Heritage Site, Gyeongju, Gyeongsangbuk-do, South Korea, Asia

Aerial image of the Royal Naval College and Queen's House, on the south bank of the River Thames, UNESCO World Heritage Site, with the Royal Observatory in the background, Greenwich, London, England, United Kingdom, Europe

Greenwich Park, the Royal Observatory up on the hill, the Queen's House by Inigo Jones and Christopher Wren's Royal Naval College, Greenwich, London, England, United Kingdom, Europe

The Royal Observatory, the Queen's House and Christopher Wren's Royal Naval College, Greenwich, London, England, United Kingdom, Europe

Royal Observatory at sunset, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

Calton Hill, National Monument, City Observatory, Dugald Stewart Monument, Edinburgh, Scotland, United Kingdom, Europe

Old Royal Naval College, UNESCO World Heritage Site, Greenwich, seen from Greenwich Observatory, with Docklands beyong, London, England, United Kingdom, Europe

Looking towards Canary Wharf and the Isle of Dogs, Docklands, from the Royal Observatory in Greenwich, London, England, United Kingdom, Europe

Old Royal Observatory, Greenwich, UNESCO World Heritage Site, London SE10, England, United Kingdom, Europe

GMT clock and standards of length, Flamsteed House, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

The original Royal Observatory dating from 1675 and site of the Prime Meridien (latitude 00, starting point of Greenwich Mean Time, Greenwich Park, Greenwich, London, England, United Kingdom, Europe

Royal Observatory, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

The Royal Observatory, Greenwich Park, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

The Royal Observatory, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

The Peter Harrison Planetarium designed by Allies and Morrison, part of the Royal Observatory complex, Greenwich, London, England, United Kingdom, Europe

The original Royal Observatory dating from 1675 and site of the Prime Meridien (latitude 00, starting point of Greenwich Mean Time, Greenwich Park, Greenwich, London, England, United Kingdom, Europe

The Octagon Room, Flamsteed House, Royal Observatory, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

Greenwich Mean Time Clock, Royal Observatory, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

The Shepherd 24-hour gate clock at the Royal Observatory, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

The Shepherd 24-hour gate clock at the Royal Observatory, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

The Octagon Room, Flamsteed House, Royal Observatory, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

Meridian Line, Royal Observatory Greenwich, London, England, United Kingdom, Europe

The 28-inch Telescope Dome, Royal Observatory, Greenwich, UNESCO World Heritage Site, London, England, United Kingdom, Europe

Old Royal Observatory, UNESCO World Heritage Site, Greenwich, London, England, United Kingdom, Europe

Trees In A Park, Royal Observatory, Greenwich, England, United Kingdom

Front view of Royal Observatory & Naval Academy in Greenwich, England

Side view of a domed building adjacent to Royal Observatory, Greenwich, England