Flanders, in northern Belgium, is an historic region noted for its medieval canal cities, famous artists, friendly down-to-earth folk and substantial cookery with a particular accent on seafood. Especially prized are tender, succulent tiny shrimp which are used to prepare everyday entress and favorite snacks.

Wherever one goes there are seafood specialties on cafe and restaurant menus. Such delicacies as small green eels, oysters, mussels, and shrimp are sold raw from shellfish carts by husky Flemish women. Fascinating arrays of cooked seafood specialties are available at delecatessen counters, sidewalk snack bars and informal eateries.

One of the best locales to enjoy the flavorful shrimp creations is along the North Sea coast, an attractive stretch of 40 miles with shallow waters, golden sand and handsome resorts. Despite the influx of tourists and the variety of vacation attractions, the old-time traditions are still followed, especially in cookery.

The name shrimp, a 10-legged crustacean, is derived from the German schremper , to shrink; in Middle English, shrimp meant a pigmy or diminutive person. Unlike those known in America, the shrimp caught in the North Sea are tiny and highly prized for their rosy red appearance and sweet sea taste.

Catching the prolific crustaceans requires skill as they hide in the sand in shallow waters and appear only at certain times. Once caught, sorting and cleaning them is a tedious job. Some restaurants hire employes who do nothing but shell the shrimp. Nevertheless, they are eagerly sought after.

The seacoast resort town of Ooostduinkerke, between Kunkirk, France, and Ostend, Belgium, pays homage to the shrimp each summer in early July with a gala festival featuring an exhibition of catching the shelfish in the traditional old-time manner.

Fishermen, dressed in oilskins, Southwesters and hip-waders, enter the sea at low tide with their horses dragging heavy trawls. Breast-deep, the horses plow through the surf until the trawls are full. Then, when towedto shore, the shrimp are emptied by the fishermen into wicker baskets attached to the horses' sides. After several passes through the surf fill the baskets, the trawls are unhooked and the shrimp loaded into carts to be sorted and sold or cleaned and cooked.

Because this type of fishing, eliminated by faster shrimp boats, was gradually fading, the town authorities instituted the annual shrimp festival in the early 1950s to keep the tradition alive. Since then it has been a great attraction.

At the festival the fishermen's catch is taken to the central square to be sold. There are band concerts, parades, illuminated ballets, a ball honoring Miss Shrimp, and a Grand Gastronomical Competition to determine the best shrimp specialties. Such culinary creations as shrimp bisque, salads, croquettes, vol-au-vents, and ramekins can be enjoyed at all types of eating places.

Two classic hors d'oeuvres or snacks, served almost everywhere along the coast, are pleasingto the eye as well as the palate. Croquettes aux crevettes , shrimp croquettes, are sold hot and crisp. Tomatoes aux crovettes , large Flemish tomatoes stuffed with tiny shrimp in a luscious mayonnaise, are served cold.

Given below are recipes for three Flemish shrimp dishes.

SHRIMPCROQUETTES (Makes 12) 3 tablespoons butter or margarine 1/4 cup all-purpose flour 1 cup light cream or milk Salt and pepper to taste 2 eggs 2 cups minced, cooked or canned shrimp 2 tablespoons fresh lemon juice Fine dry bread crumbs Fat for frying

Melt butter or margarine in a medium saucepan. Add flour and cook several seconds.Gradually add cream or milk and cook slowly, stirring constantly, until thick and smooth. Season with salt and pepper.

Separate 1 egg; beat yolk lightly and add some of hot sauce to mix with it. Return to sauce. Add shrimp and lemon juice. Mix well; cook 1 minute. Remove from heat. Beat egg white until stiff and fold into mixture. Spoon into a shallow dish or pie plate and cool. Divide equally into 12 parts. Form into 2-inch balls. Chill 1 hour.

Beat remaining egg in a small bowl. Dip each croquette in egg, then roll in breadcrumbs. Chill. Leave at room temperature 1 hour before frying. Fry in hot deep fat (375 degrees) until golden brown. Drain on paper toweling. Serve hot. SHRIMP-FILLED TOMATOES (6 servings) 6 firm, medium tomatoes 3 cups small cooked or canned shrimp (about) 1 1/2 cups mayonnaise, preferably homemade 2 teaspoons sharp mustard 2 tablespoons fresh lemon juice Salt, freshly ground pepper 1/3 cup minced chives or parsley Salad greens, washed and dried.

Cut a slice from top of each tomato.

Carefully spoon out pulp, seeds, and liquid. Invert to drain 15 minutes. Wipe shrimp dry with paper toweling. Set aside 12 shrimp to use as a garnish.

Combine mayonnaise, mustard and lemon juice. Season with salt and pepper. Add remaining shrimp; mix. Spoon into tomato shells, shaping with a spoon to form a mound over top of each. Place 2 shrimp on top of each mound. Sprinkle with chives or parsley. Serve on salad greens.

Note:The exact amount of shrimp will depend on the size of the shrimp and tomatoes. BAKED SHRIMP AND EGGS (4 servings) 6 hard-cooked eggs 1/2 pound shrimp, cooked and shelled 3/4 cup light cream 1/2 teaspoon dried basil 1/2 cup grated Parmesan cheese Salt, freshly ground pepper to taste Butter

Peel eggs and cut into shreds. Cut shrimp into small pieces, if large or medium. Combine eggs and shrimp with cream, basil, mustard and 1/3 cup cheese. Season with salt and pepper. Spoon into a shallow baking dish. Sprinkle with remaining cheese and dot with butter. Bake in preheated 400-degree oven 12 minutes, or until hot and golden on top.