Kings and queens vacationed here for nearly five centuries, the world sets its watches from here, sailors successfully navigate using a device on display in this town. All of it is a half-hour's narrated boat ride down the Thames from the Tower of London.
Across the river from the boat landing is a good view of Canary Wharf, the tallest building in the United Kingdom, at 800 feet. Canary Wharf got that name centuries ago because it is where bananas were unloaded from the Canary Islands.
But glorious history lessons about science and exploration await visitors who walk a few blocks from the river.
One of the first buildings is the handsome Royal Naval College, originally designed by Christopher Wren to be a hospital and retirement home for sailors. The building known as the Painted Hall has a ceiling mural so vast that carts with mirrored surfaces are placed in the room so visitors can look down and see the paintings, rather than crane their necks.
Beyond the college and the twin wings of the Queen's House, originally built in 1638, alter enlarged and now used as an art gallery, is a statue of William IV, at the edge of the vast lawn that is Greenwich Park. The knowledgeable use the nicknames given the king at the time of his reign: Silly Billy or Sailor Bill. Those referred to his legendary drinking and womanizing _ his mistress bore him 10 children, his wife bore none who lived _ and his obvious lack of maritime skills.
Visitors who climb the hill through the lovely green park reach the Royal Observatory. From the hilltop, you can look back to London and see the dome of St. Paul's Cathedral several miles upstream.
In the late 1600s, Greenwich was already a desirable location for London's well-to-do, adjacent to the Thames but several miles from the smoke and crowds of the working class.
It was King Charles II who decreed that his Royal Observatory be situated on the hilltop. Who else but Wren, himself an astronomer, would be chosen to design a home and work space for the royal astronomer, John Flamsteed?
More than 325 years later, Flamsteed House is still lovely to look at and intriguing to tour, because it is a museum that chronicles mankind's effort to chart time, the heavens and our place anywhere on this globe.
This last chore was largely accomplished over 40 years by a nonscientist, clockmaker John Harrison. On display are the "sea clocks" Harrison fashioned from, among other things, wood from the lignum vitae tree found in the Florida Keys. He wanted moving parts that would neither freeze nor shrink in the extreme conditions through which Britain's military and merchant ships sailed.
The clocks finally allowed shipboard navigators to determine their position east and west. The clocks' accuracy led to drawing the lines of longitude, and in the 1770s, won Harrison a prize of 20,000 pounds, a fortune then.
The continued study of measuring time is told in other exhibits, including a version of an atomic clock judged to be accurate within 1 second in the passage of 15-million years.
Outside the observatory, many visitors pose for a gag photo, with one foot in the western hemisphere and one in the eastern. They can do this because first British and then international authorities decreed that the prime meridian, the line of zero degrees longitude, would pass through the observatory grounds.
The National Maritime Museum, which chronicles the history of the greatest seafaring nation ever, is not only imaginative but fascinating. Fans of the swashbuckler Master and Commander: The Far Side of the World can easily spend an afternoon learning not only why Great Britain established the empire "upon which the sun never set" but how it was created.
Reminding visitors that the empire was created largely for profit is a brief but intriguing anthology created from scenes of movies and newsreels. Narrator of Images of Empire is Guyana-born poet/playwright John Agard, whose words are delivered in a casual singsong that belies its sarcasm:
It's plain to see
that ours is not
a self-supporting economy.
When it comes time to invade,
let's just attack
and call it "trade."
Sure we are
that Britannia rules the waves _
why count the costs
in ships and slaves?
From the 2-million-plus items in its collection, the museum displays ship's models, figureheads, ancient navigational aids and maps.
One gallery displays maritime paintings and even clips from a color documentary on vacation cruising about 1960.
Another gallery is a fascinating discussion of exploration. This is highlighted by remarkable film of Ernest Shackleton's ill-fated 1914-16 voyage to the Antarctic. His ship Endurance was locked in the ice for about nine months in 1915; visitors watch its end, crushed and sinking, as ice floes come together. Shackleton and the 27-member crew made it to an uninhabited island. He and five others then went for help. Not until August of the next year were all of them rescued.
Yet another gallery is devoted to the empire's greatest naval hero, Admiral Horatio Nelson.
Surely millions of tourists to London have passed Nelson's Column in Trafalgar Square without understanding why it was erected. The answers are in this gallery.
In October 1805, off the coast of Cadiz, Spain, the 47-year-old Nelson led an armada of 33 ships against a force of equal size from the Spanish and French navies. In about two hours, the British sank or disabled 18 enemy vessels, killing or wounding 6,000 of the enemy.
The British lost no ships, though some were no longer seaworthy, and suffered casualties of 1,700.
Among those killed was Nelson, shot through the shoulder and spine by a sniper perched in the mast of the French ship that Nelson's Victory was battling.
On display is Nelson's uniform; you can see the bullet hole below his left shoulder. If you see the Russell Crowe film Master and Commander, consider the following qualities attributed to Nelson: decisive, courageous, a leader from the front, unconventional in his attack plans, adaptable.
Nelson, who had previously lost his right arm and the sight in one eye during various battles in which he captured at least 26 vessels, once wrote: "Difficulties and dangers do but increase my desire of attempting them."
If you go
GETTING THERE: From London, you can reach Greenwich the slow, picturesque way, by a narrated cruise down the Thames, or the fast and impersonal way, connecting with the Docklands Light Railway, an elevated commuter train, from the Bank Tube stop near the Tower of London.
THE MUSEUMS: The National Maritime Museum, Queen's House and Royal Observatory are open 10 a.m. to 5 p.m. daily but are closed Dec. 24-26. At the Observatory, Flamsteed House is closed during renovations until Feb. 21. Until then, Harrison's last sea clock, known as H4, will be on display in the adjacent Meridian Building. Admission to all three is free.
FOR MORE INFORMATION: Go the Web site, www.nmm.ac.uk; each of the museums has a direct link from this home page.