SAN REMO -- 186 Main St., Annapolis. 261-2585. Open: for lunch Monday through Friday 11:30 a.m. to 3 p.m.; for dinner Monday through Saturday 6 to 10 p.m., Sunday 6 to 9 p.m.; for brunch Sunday 10 a.m. to 2 p.m. AE, Ch, MC, V. Reservations suggested. No separate non-smoking section. Prices: lunch appetizers $4.95 to $6.50, entrees $5.25 to $7.95, buffet $5.95; dinner appetizers $4.95 to $6.50, entrees $11.95 to $20.95, three-course dinner (Monday through Friday only) $19.95. Full dinner with wine, tax and tip about $30 to $45 per person.

hat mental image pops into your mind when you hear the phrase "Italian restaurant"? Red-checked tablecloths, candles in chianti bottles, cheap prices? How about "northern Italian restaurant"? The picture changes as if you'd been beamed up from K mart to Neiman- Marcus. Tuxedoed waiters come to mind, as well as rich sauces and rich prices.

How realistic is this dichotomy? Not very. Lots of restaurants that bill themselves as "northern" serve traditional southern Italian dishes, and often at a premium price. Even in Italy, regional differences among foods are blurring, just as they are in other countries. But in this part of the world, at least, "northern Italian" has become a convenient code phrase for "upscale."

Which brings us to San Remo, a year-old Annapolis restaurant that fulfills all the posh and pricey expectations we've come to associate with northern Italian restaurants. And it fulfills them well. This is a place where a premium price buys a premium product: top-grade ingredients, artful preparation, complex, refined sauces, professional service and a pretty presentation on the plate. And those plates are more than pretty,

they're full: no nouvelle asceticism here, no less-is-more artsiness. These are hefty portions for hungry people.

In a simple, understated way, San Remo is an uncommonly attractive place: small, intimate, elegant without being fussy, with quiet colors and acoustics and gentle, rosy lighting. The upscale dining room notwithstanding, there are jeans and knit shirts sprinkled amid the blue blazers and summer dresses -- this is Annapolis, not K Street, and the sailing crowd will tolerate only so much formality.

They know how to make an elegant soup here. The cream of mussel soup, always on the menu, is a subtle, mellow jewel, as is the occasionally available cream of crab, packed with snowy crab meat. Even better is a vibrant eye-opener of a tomato-basil soup, an occasional special accented cleverly with what tastes like olive oil, butter and a little finely grated cheese.

They also understand the secret of honest oyster and clam appetizers: fresh shellfish, with just enough topping to highlight -- not hide -- the natural flavor. So the clams casino and the oysters buona villa, impeccably sweet and tender, are dressed with just a bit of bacon, sweet red pepper and parmesan cheese and served in an herbed broth. The mussels, too, are first class, big and plump, in a buttery-tasting broth enlivened by minced garlic and white wine. There's also a lovely antipasto, often with asparagus, artichokes, excellent smoked salmon, marinated sweet red peppers and mushrooms.

Pastas have been tops across the board. Angel hair, the thinnest of pastas, is all too often a dense, mucky tangle, but at San Remo it's a tousled fluff, served in a silky tomato-herb-olive-oil sauce. Fettuccine primavera has enough zip in its fresh vegetables and is light enough on the cream and cheese to hold your interest, which is more than you can say for the bland, gummy primaveras served in most restaurants. Agnolotti, another cream-sauced pasta, has a bit more spark, nicely chewy and with a tasty ground veal-spinach filling.

But it is in the pasta-shellfish combinations that San Remo really shines. Look for linguine with fresh little clams, seasoned simply with salt, pepper, olive oil and garlic. Or linguine with shrimp, mussels and clams, an immense portion in a lively wine- and garlic-laced tomato sauce. But best of all is the sometimes-available linguine with fresh lobster. This is the perfect dish for those who love the taste of lobster but hate the surgical struggle normally required to eat it. An entire small, just-cooked lobster is first displayed to the diner, then de-shelled and tossed at table side with fresh linguine and a chunky, peppery, garlicky tomato sauce. The lobster flesh is wonderfully delicate and tender, its subtle flavor somehow enhanced, not hidden, by that spirited sauce.

The fish entrees have been remarkably good, substantial yet delicate. One night we had a lovely salmon special, a succulent, inch-thick wedge with capers, mushrooms and chunks of sweet Holland peppers in a delicate rose'-butter sauce. Another night's fish special was an interesting combination of swordfish and a pungent, slightly sweet sauce enlivened with balsamic vinegar.

You generally won't go wrong with the shellfish entrees, either, among them the scampi alla Julia, a special with shrimp, ham, mushrooms and shallots in a delightful marinara sauce softened with a bit of cream. But sidestep the crab meat in puff pastry, one of the few losers here. Its crab, prosciutto and mushroom filling is terrific, but the pastry crust has the texture of a damp leather glove.

Among the other entrees, the chicken with prosciutto, fontina and spinach is an interesting, well-balanced dish, and the veal piccata is exemplary. On the other hand, we found the saltimbocca dry and in a somewhat brassy sauce. Perhaps the most impressive of the entrees is the veal chop, a big, handsome piece of meat, crusty-surfaced, rosy-pink and juicy within, served in a nice sauce of reduced veal stock, sage and dry sherry.

The wines, most of them Italian, are well chosen and not outrageously priced. Two good buys, both $12.25, are the 1982 Bertani Valpolicella, a light-bodied, smooth red with a big, fruity bouquet, and the 1984 Miafiore Soave, a light, crisp, clean-finished white.

San Remo's desserts, made in house, are exceptional, and the portions are big enough for sharing. Look especially for the dense, buttery rum cake, and for both kinds of cheesecake -- the fluffy-yet- intense Italian style and the deceptively velvety chocolate variety, with a real chocolate wallop.

The most frequent question we get during the summer is where to eat on the way to or from the beach. Here's a stopover where you can get a memorable meal instead of just sustenance. But be sure to shake the sand out of your Topsiders and run a comb through your hair. And bring your credit card. ::

Mark and Gail Barnett are free-lance restaurant critics. Phyllis C. Richman is on assignment.