Stand with one foot in the East and one in the West astride the Greenwich Meridian and set your watch by the red 'Time Ball' that drops each day at 1300hrs precisely and has done so for 170 years. A recent addition is an electronic news bulletin board, which transmits the news headlines from around the world.
Other nautical attractions include the National Maritime Museum, the Cutty Sark (a 19th Century tea clipper) and the Gipsy Moth, a tiny yacht which became a potent symbol of British sailing heritage after being sailed solo around the world.
There's a laid-back feel to Greenwich. It's the sort of place that you can while away several hours browsing market stalls - crafts, antiques, records, bric a brac and, most famously, vintage clothing. Then you might pop into a riverside pub for lunch and find yourself still there in the evening listening to some mellow jazz.
Things to see and do
The Royal Observatory
National Maritime Museum
The Queen's House
Greenwich Peninsula Ecology Park
The O2 Arena
The Cutty Sark