JIMMY CANTLER'S RIVERSIDE INN -- St. Margarets, Maryland, 301/757-9888.

A white clapboard house by the Pepsi sign on the edge of Mill Creek is Jimmy Cantler's Riverside Inn.

Although it's about five miles from Annapolis, few tourists, or even Annapolitans, are likely to find it. But it is special because it's a seafood restaurant owned by a waterman who catches the crabs, fish and oysters served there.

Route 50 to Annapolis passes by stretches of stick woodlands and farmlands asleep for the winter except for the sheep and cows picking their way along the dry grass, and now and then a chicken coop losing the battle with gravity and falling into the ground. Beyond Annapolis on the way to Bay Bridge, a huge red windmill is attached to a pancake house; that's the turn for Old Mill Bottom Road. Then a right on St. Margarets Road leads to another landmark, a country store in the throes of identity crisis: It's Easter's Deli from the side; head on, it's Sandy's Country Store. A hard left there, then the first right on to Forest Beach Road will take you to St. Margarets, Maryland. Don't bother looking for it on the map.

Riverside Inn is at the end of the road. On a chilly Saturday afternoon, local kids come by to play Galactica, and the booping of electronic games competes with Ray Charles singing "Born to Lose" from the jukebox. Over the bar dangle red cupids, tickled by the air, and underneath the men talk about putting down rock salt and what happened once with some woman. A gas station attendant got Sue on the payphone and asked her to "tell her I'm on my way," then sat back down on the red plastic barstool for another can of beer.

Behind the bar is a "Welcome Shipmates" sign -- the watermen come in when the weather's bad -- along with two fake lanterns, a barometer and a TV set with a college basketball game on the screen. "That was a foul there!" one customer called out to anyone listening. "Oh he hurt his head -- he ain't hurt much. Haw, haw."

In season, large crabs go for $12 a dozen, and when you look around the room at the communal tables you can imagine how noisy it must get here in the summer with all that hammering and beer drinking. But right now there are fresh-shucked Chesapeake Bay oysters, $3 a dozen, lying quietly on a bed of ice on a round blue plastic tray.

Blackboards on the walls are neatly printed with the menu, and one particular item interested us: Captain Louis seafood platter. Who was Captain Louis, we wondered. "That's Dad," said Marie, the waitress. "My brother owns the place."

Of eight brothers and eight sisters, Jimmy Cantler said "about six" are involved in his operation.

"Used to be a bar with a pool table. Used to be just a bar for watermen and a few other roughies fighting and gambling. I got rid of that, changed the clientele. It's a family place.

"We were all born on this point," he said. His grandfather bought land in St. Margarets in 1921. "He worked on the water, too," said Cantler, "his father and all his brothers." And now Jimmy's son, who's 20, works on one of his father's oyster boats.

He's got four boats, and they work in spite of the ice and so far this winter they've only been frozen in for three days.

For days when the fish aren't running and softshells aren't available, they "freeze ahead." There seems to be quite a difference between frozen and what Cantler calls "fresh frozen." At Cantler's the rock platter is $6.50 -- the most expensive platter on the menu. A small rockfish, lightly fried, brought back memories of freshly caught fish, in a West Virginia cabin where the host went outside to the stream and caught breakfast . . . the fish unbelievably sweet, the white flesh flaking just so . . . and if you could have it like this, you'd never eat anything else. Cantler said it was fresh frozen since fishing is slow right now, and that he couldn't tell the difference between it and fresh, and that made two of us.

He expects to have fresh fish in about two weeks and to start serving steamed crabs by the middle of April.

Oyster stew was a lightly seasoned buttery liquor, with many potatoes that still had the fight in them, but unfortunately only two oysters in the bowl. Soup is a chance affair, and we hoped the next guy got the rest of our oysters.

Down a flight of wooden stairs to the waterfront, you can see the crab operation in hibernation, the shedding boxes where in summer the crabs are put to shed their shells and become prized softshells. Nowadays, Cantler is busy all the time getting ready for the warmer days, painting, working on the boats. In the summer, he said, "I crab some. We buy peelers and shed a lot. That's a 24-hour-a-day job, watching them."

And he runs the restaurant, which he started about six years back. "I would've never got in it," he said, "if it had been on land."