ALEXANDRIANS have always known how to party hearty, so this weekend's celebration of the town's 250th birthday will be right in character. This is, after all, the place where George Washington kept a town house so he could sleep off an evening of dining, tippling and gambling instead of facing the long ride back to Mount Vernon.

Because it offered the biggest and best harbor at the head of navigation of the Potomac, Alexandria early on became one of North America's leading seaports. The colonial town played host to legions of settlers, travelers, merchants and sailors, all eager for food and drink and a place to lay their aching heads.

John Alexander, the Scotsman and Stafford County planter after whom the town was named, found the site so nice he bought it twice. Mistress Margaret Brent, a kinswoman of Lord Baltimore and an early advocate of women's rights, was granted 700 acres. In 1669 another and inadvertently overlapping grant was issued to English sea captain Robert Howson. Alexander had to buy both grants to get clear title.

Tobacco was the main article of export at first, but its cultivation quickly exhausted the soil. Revitalized by shipments of guano from Peru, the region became a major supplier of wheat and flour to Europe, particularly Spain and Portugal, which reciprocated with the oceans of port, sherry and madeira that lubricated upper-class social intercourse. Hewers of wood and drawers of water made do with beer, cider and eventually the more ardent spirits derived from the triangular trade of rum, molasses and slaves. By the eve of the Civil War, Alexandria had achieved the sorry distinction of being Virginia's leading slave-trading center.

At the turn of the 18th century new taverns were opening almost monthly, and then as now the proprietors strove to distinguish their establishments from those of their rivals. Potomac delicacies such as sturgeon and herring roe were liberally served out. Watermens' boats arrived daily with Chesapeake Bay specialties, especially the fabled oysters that would eventually be driven to the brink of extinction by disease and overfishing.

The diamondback terrapin became a favorite delicacy, along with ducks, geese and other waterfowl. The blue crab, supreme culinary adornment of the Bay, is oddly uncommon on period menus; the locals apparently were slow to appreciate the gustatory virtues of the "beautiful swimmer."

The wave of gentrification that has swept Old Town in recent decades echoes the efforts of earlier establishments to move up in class. William Page in 1788 sought to draw fat cats to his Merchants Coffeehouse by supplying out-of-town papers, the latest national and international commodity price lists and mail service to London.

Scots figured largely in early Alexandria entertainment and catered to all classes. John MacLeod ran a microbrewery on Royal Street at which he produced beer "of the first quality" for consumption on premises, takeout or home delivery by the gallon. The attractions offered by William McKnight, who gave up cabinetmaking for innkeeping on King Street, in 1792 included a wax model of Jerusalem, and the following year a pair of bison. Later he offered a performance by "Mr. Nesbit," whose slack-wire balancing act involved swords, pistols, a drum, a full glass of water and 15, count 'em, 15 eggs. Sadly, no further details are available.

Happily, there remains one authentic remnant of the town's first hedonistic heyday. Gadsby's Tavern, at 138 N. Royal St., which in its day was ranked with the finest establishments in the country, has been preserved, restored and revived as both a museum and a restaurant serving period dishes in the period manner (which is to say with a good deal of jollity and considerable crowding). The museum, whose staffers are masters at re-creating period ambiance, will be hosting a series of events throughout the summer and fall (see list, at right).

John Gadsby, an Englishman who first ran the Union Tavern down by the riverside, took over what he renamed the City Tavern and Hotel in 1796. In those days "hotel" was a fancy French word, and Gadsby adopted it to indicate that he was abandoning his established "nautical custom" for the patronage of the uptown gentry. He got it, although the place was universally referred to simply as Gadsby's. Gadsby's became The Place for such celebrations as a birthday party for George Washington and a dinner and reception for president-elect Thomas Jefferson. Gadsby's had such a wide and lasting reputation that half a century later Mark Twain titled one of his tales "The Man Who Stopped at Gadsby's."

It wasn't all party, party, party by any means, but the city has sound precedent for calling itself "The Fun Side of the Potomac."

This easygoing spirit has resulted in Alexandria passing up two excellent opportunities to become a battlefield. Although it was home to two very famous warriors, Washington and Robert E. Lee, the city's central war memorial is "Appomattox," the defeated soldier who stands slumped at the intersection of Duke and Washington streets.

When opportunities for martial heroics have arisen, the city has passed. In 1781, when the Marquis de Lafayette passed through town on his famous long march from New York to the decisive battle at Yorktown, he complained to Governor Jefferson that he was unable to procure "a single wagon" for his supply train from the townspeople, who apparently still were hedging their bets on the outcome of the Revolutionary War.

This although the "taxation without representation" that sparked the war began in Alexandria, where in 1755 five royal governors met with British General Edward Braddock at the Carlyle House to discuss ways to finance the French and Indian War. Parliament agreed to their proposed tax on "all His Majesty's dominions in America," and the rest is history. (In 1820, during Lafayette's triumphal return tour of the United States, the city wined and dined him for a month, and he could have had any wagon in the place.)

During the War of 1812, Alexandria passed up a perfect chance to be blown away by a British squadron that sailed up the Potomac and took the town en passant on their way to burn Washington. Alexandria had loaned the federal government $35,000 to underwrite fortification of the river but little had been done. So the Common Council sent a delegation downriver to surrender the town to Capt. James Gordon, whose troops spent five days looting, but not burning, the town. They hauled away a king's ransack in goods, grain and gear; the losses, exacerbated by the Panic of 1816, put paid to the city as a seaport.

Not until the beginning of the Civil War would the harbor again be forested with shipmasts, and once again it was the vessels of an occupation force. In April 1861 Alexandria, hopelessly exposed to the power of the federal government, surrendered to Union troops advancing from Washington by land and water. Exactly two shots were fired, in a sad and murderous opera bouffe encounter between Union Col. E.E. Ellsworth and James Jackson, proprietor of the Marshall House. Ellsworth rushed to the roof of the place to tear down the huge Confederate flag flying there; as he bore the banner down the stairs Marshall shot him and was shot down in turn.

The occupied city became a principal staging area for both the Union army and navy, bringing a melancholy revival of prosperity to carpetbaggers and some citizens and imprisonment or exile to others. It also became a major medical center whose streets literally ran with blood when the horrendous hospital trains rolled in from battle after battle. Alexandria was occupied longer than any other southern city during the war, and the influx of hundreds of thousands of soldiers, in training or in passage, wreaked havoc.

Gen. John P. Slough, Union commander of the town, ordered a curfew and a halt to all sales of beer, wine or liquor. It didn't work much better than Prohibition, but it did calm things down considerably, as Slough pointed out when town merchants complained about the restrictions:

"There had been for days previous, a reign of terror in Alexandria. The streets were crowded with intoxicated soldiery; murder was of almost hourly occurrence and disturbances, robbery and riot were constant. The sidewalks and docks were covered with drunken men, women and children and quiet citizens were afraid to venture into the streets and life and property were at the mercy of the maddened throng -- a condition of things perhaps never in the history of this country to be found in any other city."

After the Civil War the city subsided into sleepy gentility and gentle decay that lasted until World War II. Until the late 1960s you could drive along almost any sidewalk in Old Town from sundown to sunup without menacing any living thing but the odd dog, cat or rat. Expansion of the federal government fueled a building boom that first leapfrogged the city and then led to gentrification of what had been in many cases giveaway slum houses. Urban renewal -- and horrified reaction to its excesses -- energized a renaissance so sweeping that now you can hardly drive down the streets, much less the sidewalks, at any time of day.

Again, as in the beginning, there's a hot time in the old town tonight.

CAPTION: Historic markers, clockwise from left: "Appomattox" looking defeated; a tall ship at the seaport; the city celebrates its Scottish ancestry; musicians in the George Washington Parade.