Dublin's layers of history and culture reward even the hurried traveler

It was nearly closing time for the National Museum. I had been running around Dublin since early morning, trying to see as much as I could in my one full day in the city. But I couldn't pass by without stopping in, even though half of the 100-year-old building was closed for repairs.

A few years ago I had stood elbow to elbow with the throng in the Boston Museum of Fine Arts to view the traveling exhibit of Irish antiquities. Now, I had the opportunity to see some of the exquisitely crafted relics again in their own homeland.

My intention had been to take a quick peek at the Cross of Cong and a few of the other golden treasures of the Celtic period, then scurry through St. Stephen's Green before meeting other tour members for dinner. But a uniformed museum guard saw me jotting down a few notes and came over to see if I had any questions he could answer.

To say he was the epitome of a jolly Irishman would be no exaggeration. Every statement was punctuated with a laugh, whether he was explaining that the 52 -foot dugout canoe from Galway Bay was cut from a single tree, or showing off the beautiful restoration work being done on the President de Valera room. He also proved to be a one-man file folder of every piece in the museum. ''These bronzes have enamel work that can only be seen with a magnifying glass, ha, ha, ha.''

He walked me around the museum as if he were in his own living room showing me pictures of his family. But even beyond his delight in his job, he had a quality I had sensed in other Dubliners - a pride in his heritage.

Dublin is like those Chinese boxes that you open and there's another box inside, and another inside that, and so on and on. The lovely old Georgian city surrounds the older Norman center built on the Viking capital over the Celtic community. The Georgian box itself sits inside the turn-of-the-century Dublin of James Joyce, when much of its elegance was hidden behind what he described as the ''scrupulous meanness'' and paralysis of spirit that the city had fallen to in its 19th-century poverty. But there's another box outside that - of modern commercial buildings, including high-rises constructed in a race to modernize during the 1970s.

In some ways, Dublin is also like a city just beginning to wake up from a Rip van Winkle sleep. Although Joyce might be dismayed by the changes of the last decade made in the name of progress, he would undoubtedly be heartened by the signs that the city seems finally to be coming of age and beginning to appreciate itself. Georgian mansions that had become tenements are being restored, their rococo beauty uncovered behind years of grime and neglect. Zoning laws now set strict height limitations. There's even one new office building on Leeson Street near the canal that has a lovely Georgian-style facade. What had been known in Joyce's day as the worst slums in Europe have been replaced with decent public housing.

The challenge to the visitor is to look beneath the outer box of modernity to find the Dublin that is past and present in one, part Joycean, part Georgian, part Celtic, Viking and Norman, and cosmopolitan European on top of it all.

The Irish capital is often an ''if this is Thursday, this must be Dublin'' kind of city, a one-day stopover on the itinerary. It's where the tour ends, or a since-we're-going-all-the-way-to-England-let's-see-Ireland-too destination. So you, too, might find yourself standing somewhere by a newsstand with a recently purchased map that means little to you. The street patterns remind you of a Pac-Man game, except the lines aren't so straight, and you're beginning to understand why the Irish have always felt so at home in Boston.

If you are a Joycean scholar, you might know enough about the city to keep you happily poking around for days. If not, you might end up like me, circling the city three times before realizing you've been lost in the same place already.

Actually, the half-day bus tour (from Central Station on Store St.) is not a bad way to get started, as long as you bring a map along so you can keep your bearings. Then, find the Tourist Board office on O'Connell Street and pick up a copy of their walking tour. The tour supposedly takes about three hours, but you would want to plan much more time for stopping in shops or museums, or just plain people-watching. This is a special treat here, because even though Dublin is the capital and largest city in Ireland, I found the people here as friendly and welcoming as any in the rest of the country.

Do stroll down Grafton Street, perhaps stopping in Bewley's for a lunch of steak and kidney pie. Don't miss exploring the shops on the quays along the Liffey. The Dublin Woolen Company, on the north bank by the Halfpenny Bridge, has a particularly good selection of tweed caps and scarfs, as well as Aran sweaters and fabrics. Nearby, at 39 Lower Ormond Quay, is Michael Giffney's stamp and coin shop, where you can also find old post cards of Ireland and have a bit of conversation on your Irish heritage with the proprietor.

For the music-minded, Waltons', near Parnell Square on O'Connell Street, has records, sheet music, and Irish instruments.

Dublin evenings, of course, are filled with theater and music of all types. Dublin magazine is a good source for what's playing where.

For the adventurous, the creaky old Brazen Head Hotel offers authentic Irish folk entertainment. The present building was chartered in 1688, but there has probably been some sort of establishment here since the early Norman days.

They say if the walls could talk, you'd hear many a tale of conspiracies hatched and rebellions plotted in its rooms. All summer, rain or shine, jam sessions go on outside in the courtyard. As the cab pulls up, you'll wonder what you're getting into, as much of the rest of the block is undergoing urban renewal. But walk through the archway between the piles of rubble and you can hear some of the best Irish music around, everything from jigs and reels and more modern ballads to the unaccompanied sean nos (old style) singing. The crowd, mostly young, is congenial, but be prepared to sit on the ground. You might bring along a newspaper or magazine to sit on, and definitely dress down - jeans would be appropriate.

It's also a good idea to ask your cabdriver to come back for you at 11:20 (the Brazen Head closes at 11:30, like most Irish public houses).

With so much demolition and construction in the area, finding a phone could be a little tough. He'll be happy to oblige.

The Brazen Head is in the original part of the city, south of the Liffey and west of O'Connell Street. Some of the medieval city still remains, including Christchurch Cathedral, Dublin Castle, and sections of the old wall. The cathedral is noted for its fine peal of bells. If you're in town on a Friday night, reserve a table for dinner at the Lord Edward, one of Dublin's finest restaurants, just across the street. From about 7:30 to 9, you can hear the bellringers practice change-ringing patterns as you enjoy an elegant meal of seafood and brown bread.

The Celtic name for Dublin was Baile Atha Cliath (pronounced something like ''Blah Clear''), which means ''the town of the hurdle ford.'' You'll still see the name on good idea road signs. When the Danes invaded in the 9th century, they settled here, renaming the town Dubh Linn, or Black Pool. In the 12th century, the Normans pushed the Danes north across the Liffey, and in the 13th century erected Dublin Castle as their seat of government. The castle remained the principal seat of British administration of Ireland until 1920, and the English-speaking area of the east coast of the island, with Dublin as its capital, became known as The Pale.

In the mid-18th century, a time of economic prosperity, the wealthy Anglo-Irish began to move north and west of the medieval city, building a new Georgian Dublin. The Wide Streets Commissioners, the first official town planning authority in Europe, was established in 1757, and the broad avenues such as O'Connell Street, Upper Merrion Street, and Baggot Street were laid out. Uniformity in building elevations was enforced, and the city took on the grace and style of the age of reason. Curves and lines were combined in the street patterns, with crescents opening into squares. Bridges spanned the Liffey and Grand Canal, all with a spirit of sensible elegance.

The modern age has not improved on those qualities - the street patterns were not intended for ease of cars and buses, and newer buildings aren't always in keeping with the character of the old. But wandering around between Fitzwilliam and Merrion Squares, over to the canal and back up Mount Street, you might still be able to catch the vision of the Georgian builders.

If you've seen the popular poster of Dublin Doors, you'll recognize many of them along Pembroke West and Fitzwilliam Square. The plainness of the buildings attached to them might come as a surprise. But the famous Dublin door is the whipped cream leaking ever so slightly out of the cream puff, giving just a hint of the goodies inside.

For the Georgians, the plain brick facade was only the packaging for the most imaginative of confections. Inside many of these homes are ceilings dripping with cherubs and Greek gods in the finest plasterwork of the day. Glistening wood and metalworked banisters climb up from opulently tiled floors, attesting to a period when life, politics, and the arts had a vitality in the city, and classical culture was in vogue.

Most of this remains hidden to the visitor, who will have to be content with taking close-up photographs of the brass door knockers. One place that does permit visitors is the mansion of Belvedere College, at 6 Great Denmark Street, during holidays and after school hours. Here, in what may well be one of the finest Georgian interiors in Dublin, James Joyce received his traditional education amid the mythological ceiling figures of Michael Stapleton, one of 18 th-century Dublin's famed stuccodores.

No less notable are the Georgian public buildings. The Customs House, the Four Courts, and the General Post Office were burned during fighting early in the century, but have been carefully restored. Trinity College houses the Book of Kells, the 9th-century illuminated manuscript of the Gospels. Although the setting is not nearly so dramatic as in the traveling United States exhibit with its black velvet backing and spotlighting, it seems appropriate. Looking up at the massive shelves of this venerable library, you can't help thinking in awe of the poets and scholars who have studied here.

But to see the everyday face of Dublin, stroll through St. Stephen's Green before dinnertime, when the sun is just starting to catch the windows on the Shelbourne, the grand dame of Dublin hotels. If the Dublin doors are a glimpse of the rococo within, Stephen's Green is a peek at the private lives of the people. A wedding processional might pass by. You'll see mothers pushing prams, or a father spending a precious hour alone with his toddler.

I had hoped to top off my Dublin day with a big bowl of Irish stew, but when I asked a group of young people where I might find it, they laughed and said Irish people don't want anything so mundane when they go out to eat so I'd be hard pressed to find it anywhere.

''Why don't you eat what we eat?'' they suggested.

''What's that?'' I asked.

''Pizza!''

Clearly Dublin has come of age. Practical information:

Aer Lingus has flights from New York and Boston to Dublin, with one stop at Shannon. Northwest Orient and TransAmerica fly into Shannon. Aer Arann has service from Shannon to Dublin.

Shannon International Hotel is offering a stopover package for $64, including a medieval banquet at Bunratty Castle and full Irish breakfast. A two-day package includes free golf.

Ms. Hand's tour was sponsored by the Irish Tourist Board and Aer Lingus.