"REMEMBER the Alamo," Texan Sam Houston shouted more than a century ago, and, as we all dutifully have done so, his battle cry proved to be a remarkable blessing for the once dusty outpost and now blossoming city of San Antonio that has grown up around that monument to stubborn courage.

San Antonio is synonymous with the Alamo, where in 1836 a small garrison of Texas independence fighters, Davy Crockett and Jim Bowie among them, fought to the death rather than surrender to the overwhelming odds of a Mexican army led by Gen. Santa Anna. A substantial portion of the fortress remains, dominated by the chapel where the women and children who survived took refuge.

The Alamo occupies a broad plaza in the very heart of San Antonio's business district, which is fitting since it also is at the heart of Texan history ("The Cradle of Texas Liberty"). Houston's cry has echoed over the decades, and hordes of sunbaked tourists, Texans and outsiders alike, troop steadily through the gates, quieting abruptly in the reverential atmosphere within the cool adobe walls. Remember the Alamo, and we remember San Antonio.

But, just for a moment, forget the Alamo. Then what is San Antonio?

It's a surprisingly delightful and attractive city that offers much to the tourist, a Texas metropolis with a Mexican village flavor that is both fun and easy to explore on foot. It is also a city with aspirations. Next week, it is inaugurating a major international performing arts festival, the San Antonio Festival, with an impressive roster of big names from the classical, jazz and pop stages. Its promoters hope it becomes an annual event that puts the city on the world's cultural map.

And not the least of its attributes, San Antonio is a wise city that has turned its unimpressive location on the banks of a sleepy Texas plains river into a huge asset, a stunning garden of food, song and drink called Paseo del Rio or River Walk.

See the Alamo, but linger along the San Antonio River.

My first problem was to find the river. Twenty years ago, I had passed through San Antonio and was entranced by the colorful sidewalk cafes and bars that line its banks as it flows in a broad U-shaped loop through the city center. And back in my preschool boyhood, my father had canoed my sister and me along its waters while he temporarily was stationed in San Antonio during World War II.

The river, not the Alamo, was what I mostly remembered of the city. So even before unpacking, I rushed out of the century-old Menger Hotel next to the Alamo, passing it by in search of a river pub to toast our weekend holiday. The river was nearby, I knew, but where?

Up one busy street and down another I searched through the, well, drab--no, seedy--collection of downtown department stores, office buildings, beer joints and porn shops. And then my memory cleared. The river is one level down, below the bustle of city traffic, a dozen stone steps from almost anywhere to a hidden canyon of charm and gaiety shaded by cypresses, oaks and willows.

Overhead tower skyscraper hotels, but at riverside the setting is Spanish colonial at fiesta time. For more than 20 blocks, cobblestone sidewalks line each side of the silky river, crisscrossing it a dozen times in quaint arching bridges. Miniature waterfalls tumble down lushly landscaped slopes, strollers wend their way past clusters of bright-colored cafe' umbrellas and music (mariachi, jazz, rock) drifts from inviting doorways.

On the river itself, barely a stone's throw in width, tourists in open barges drift peacefully by watching the watchers on shore. If you are a group, you can get one of the river restaurants to cater a meal aboard, dining by the twinkling lights overhead, while guitarists strum "Cielito Lindo." The crowds thin out only in the early hours of the morning.

Several hotels open onto River Walk, which means you can, if you want, go from room to boutique to restaurant to symphony to hotel again and never emerge from this agreeable retreat.

"San Antonio will have a festival at the drop of the hat," says a city spokeswoman, and the calendar seems to bear her out, with celebrations throughout the year reflecting the city's varied past: the Wild West, its dominant Mexican heritage, the strong influence of German and other European immigration into the region in the mid-19th century.

In early February, thousands of Texans in distant communities traditionally mount their horses and point them toward San Antonio in a dozen trail rides, some lasting several days, for the 10-day Stock Show and Rodeo. It's big doings with a lot of whoopie. This year one group of would-be cowboys reportedly got under way behind a Lone Star beer truck blaring country-western music, three covered wagons filled with beer and a flatbed truck toting portable toilets.

In April, there's Fiesta week, when the river becomes a parade route for brightly decorated barges, and "Night in Old San Antonio" is a four-night party of ethnic music, food and dance staged in La Villita, a reconstruction of the little village of tradesmen and camp followers that grew up on the outskirts of the Alamo. More than 100,000 visitors crowd the fountain square, spilling over into the adjacent River Walk, and hotels are booked up months in advance.

And next week, the San Antonio Festival joins the list. Among the big-name performers on the three-week schedule (May 14-June 5): soprano Birgit Nilsson; the Berlin Opera and Ballet; Metropolitan Opera stars Robert Merrill, Anna Moffo and Frederica von Stade; and jazz stars Ray Charles and Sarah Vaughan.

With the cowboy mystique still a strong force in Texas, says a leader in the city's arts world, the state suffers from a "cultural insecurity." But they're spending money like rich Texans to overcome it.

Despite the sluggish economy nationally, in San Antonio (population about 1 million) one senses a city on the move, and the festival, with more than 70 events scheduled, is only one of many indications.

Major hotels such as the Marriott and Hyatt Regency have sprung up downtown to capture the booming convention trade, and several older ones (the Gunter, the St. Anthony--to become the Inter-Continental San Antonio) have been lavishly renovated. Tourism--an estimated 9 million visitors last year--is big business here (as is the military, with five installations, including Lackland Air Force Base, the basic training center for all Air Force recruits; you see a lot of uniforms downtown).

There are big plans afoot to redevelop the decaying center-city site of HemisFair '68, San Antonio's world's fair (a survivor of that exposition is the Tower of the Americas, a restaurant revolving 500 feet above the city). Young professionals are moving back from the suburbs, restoring the once stately Victorian mansions of German merchants in the 25-block King William district. (Many had become tenements, but now they are a tourist draw.) The Majestic, a grand old movie palace--the kind where balconies and alcoves drip with plaster curlicues and the ceiling is a blue sky of stars--has been preserved as the Majestic Performing Arts Center for concerts and touring musicals.

And in 1981, the sprawling, castle-like structures of the old yellow-brick Lone Star brewery were transformed by twin glass elevators, skylights and a turret-to-turret glass skywalk into the dazzling San Antonio Museum of Art, where the building itself (like the East Building of the National Gallery) rivals the collection of contemporary works.

"Dallas and Houston the two Texas cities larger than San Antonio have had their time," says Mark Lane, the young director of the Witte Museum, a touch-and-do family museum of regional history and natural history. "In the last two years, San Antonio has taken off. There's an optimism here." As a newcomer, he sees it in his efforts to raise funds for the Witte. "It's not easy, but it's not as hard to raise a million as I expected."

The impetus for change, Lane believes, is coming from many of San Antonio's young and energetic professionals. Energetic is the right word for Kathy Smith, the wife of conductor Lawrence Leighton Smith of the San Antonio Symphony. A mother who participates in the city's busy cultural life, she's also a full-time medical student. On any concert night, she's the woman at orchestra front studiously flipping note cards while the violins play.

"Clang-clang. Clang-clang."

Trolleyman David Tate, hand clutching the bell rope, is impatient waiting for the straggling tour group to board Old 300, a trolley parked outside the Museum of Art. The car is one more renovation project, undertaken by trolley buffs, all volunteers. Lovingly rebuilt and polished to high gleam, No. 300 was one of 25 streetcars that traveled San Antonio's streets until 1933. Put back in operation last October, the car makes a short run (twice weekdays, four times weekends) twixt mind and body. Board at the museum and descend behind the gates of the Pearl Brewery. If you've hit it right, the sampling room is open.

"Clang-clang." The trolley is approaching a street intersection. Tate swings off with a red flag. All traffic stops when Old 300 is passing by.

At La Villita, on the edge of River Walk, the Little Rhein Steak House, occupying what is reputed to be the first two-story building in San Antonio (dating from about 1847) and once a German-style saloon, serves up superb steaks in an elegant 19th-century setting.

Overlooking the river, the Bayou (San Antonio is not so very far from the Gulf Coast) offers scrumptious braised jumbo shrimp and artichoke hearts in a light wine sauce. The view is just as delicious.

And a few blocks down the street at El Mercado, a lively Mexican-style market place selling fresh produce and handicrafts, La Margarita's fajitas (spicy charcoaled beef topped with guacamole, tomatoes and onions and wrapped in a tortilla) sizzle and pop from the kitchen while the mariachi band blares in accompaniment. The restaurant is popular and noisy, and the music stops only for a minute, when singer Jose Feliciano, fresh from a concert at the Majestic, is escorted to a corner table with a round of applause.

The Menger is the old hotel (with a modern wing), opening in 1859 only 23 years after the fall of The Alamo. Lillie Langtree, Sara Bernhardt, O. Henry, Ulysses S. Grant and John J. Pershing were guests in their time. The bedrooms in the old wing have been restored in 19th-century decor and filled with antiques. The Victorian public rooms are sumptuous, the tiled patio a delight, but the richly wood-paneled Roosevelt Bar is where the ghosts of Old Texas are felt most strongly.

When the cattle herds headed up the Chisholm Trail, this was the hub of Texas cattle-country, the site--so the hotel claims--of more cattle deals than anywhere else in the state (a handshake over three fingers of rye sealed the agreement). And here in 1898 is where Teddy Roosevelt, giving the place its name, recruited many of his Cuban-bound Roughriders.

Among Texas cities, writes the magazine San Antonio Living, "Houston is envied, Dallas is respected, but San Antonio is loved."

In the 1700s, Franciscan missionaries built 36 missions in Texas to bring Christianity to the Indians, and The Alamo--known as Mission San Antonio de Valero--was the first in 1718. Flourishing for a period, it was later abandoned, eventually to become the poorly fortified garrison for the 183 doomed Texas independence fighters. But the adjacent countryside was also the site of four other missions within a few miles of each other, and they have become the San Antonio Missions National Historic Park on the outskirts of the city, linked by a marked roadway, the Mission Trail.

The largest, Mission San Jose--completed at about the time of the American Revolution and still serving an active parish of 900 families--was considered the "Queen of the Missions of New Spain" for its simple beauty. Here on a Sunday morning is a fitting place to conclude a visit to San Antonio.

At first there is tranquility in the surrounding gardens as you reflect on the city's historic riches. And then at noon, like a child in church unable to restrain his exuberance, the mission compound explodes in the sound of joyous hymns sung out by the guitars, violins and trumpets of a 15-piece mariachi band calling parishioners to mass.

A city reverent of its past but full of the gaiety of life, that's the San Antonio to remember.