Following an ambitious £15-million renovation the Royal Observatory is now divided into two sections.

The northern half deals with time and is contained in the original Observatory that Charles II had built on a hill in the middle of Greenwich Park in 1675, intending that astronomy be used to establish longitude at sea. It contains the Octagon Room, designed by Wren, and the nearby Sextant Room where John Flamsteed (1646–1719), the first astronomer royal, made his observations and calculations.

The globe is divided between east and west at the Royal Observatory, and in the Meridian Courtyard you can place one foot either side of the meridian line and straddle the two hemispheres. Every day at 1pm the red time ball at the top of the Royal Observatory continues to drop as has done since 1833. You can get great views of Greenwich and spy on your fellow tourists at the same time by visiting the unique Camera Obscura.

The southern half is devoted to astronomy and includes the 120-seat state-of-the-art Peter Harrison Planetarium, with a digital laser projector that can show entire heavens on the inside of its bronze-clad roof and is the most advanced in Europe. Galleries here trace the history of astronomy and interactive displays focus on such subjects as meteorites, space missions and the effects of gravity.