Open Monday through Saturday, 11 a.m. to 11 p.m.; Sunday, 11 a.m. to 9 p.m. No credit cards. Reservations except Saturday after 6 p.m. Prices: Main courses $4.75 to $8.75. Steamed crabs, at last check, $10 to $15 a dozen. All-you-can-eat crab feasts Monday through Saturday, 11 a.m. to 9 p.m., $10.50. Open Tuesday through Thursday, 4 to 10 p.m.; Friday and Saturday, 11 a.m. to 11 p.m.; Sunday, 11 a.m. to 10 p.m. No credit cards; personal checks accepted. No reservations. Prices: Main courses $4.95 to $8.95. Steamed crabs, at last check, $10 to $12.50 a dozen. All-you-can-eat crab fests daily except Sundays until supply is gone, $10.50.

There is nothing like a Southern Maryland crab house except the one next door. Forty miles south of Washington off Route 301 on Popes Creek, are two side-by-side crabhouses that take close examination to tell the difference between them.

I asked the waitress at Robertson's what was the difference between the two. "Both are the same, except this is better." The bartender at Captain Drinks' was more succinct: "This is better."

Both are shellacked pine caverns lined with tables covered in in brown paper and set with bottles of vingegar capped by pleated paper cups. Captain Drinks' vinegar bottles are nicer; Robertson's also has baby food jars of cayenne pepper and stacks of brown paper towels on the tables. Captain Drinks' has more booths; Robertson's has more long tables. Both have a row of tables along the windows that hang over the Potomac and show a panorama of pier and bridge. At Robertson's the windows are elbow level and have green plastic shades; Captin Drinks' only come down to your shoulders -- no shades. The waitresses at both, one would guess from a glance, all go to the same hairdresser.

Robertson's, they will tell you at both restaurants, is the more crowded of the two.

If you are looking for steamed crabs and pitchers of beer, which is why you should be driving so far anyway, either one will do. You might as well choose the less crowded. At last check, crabs were $10 and $12.50 a dozen at Caaptain Drinks'; $10, $12 and $15 at Robertson's. They looked of comparable size at the $12-$12.50 level, and that we tried were fat and meaty and sweet. Midly peppered, hot and juicy were the crabs at both places, though Captain Drinks' has salted them more. In case you don't know how to eat crabs and are shy, Robertson's has placements with instructions, but anybody around will give you an unscheduled demonstration.

The signigican differences in the two restaurants are in the deep fryer areas of these kitchens and in the soup pots.

A seafood platter at Robertson's -- at $8.75 it is 20 cents cheaper than its competition -- is one of the wonders of Southern Maryland. A crabcake (too heavy with breading and more peppery than the deviled crab), a few fried shrimp and scallops, and a softshell crab are buried in an avalanche of fried oysters, a full two dozen of them on our platter, oysters that had been fried to a crunch in cornmeal batter and stayed juicy inside. With these are a mountain of very creamy coleslaw and too-sweet but nevertheless good potato salad, if you are smart enough to skip the frozen french fries and canned string beans. No lesser a sight was the deviled crab platter, two well-browned mounds of faintly peppered crab, bigger and better (as well as less peppery) than the crab cakes, for $7. Softshell crabs were left unbattered and lightly fried, puffed into a tangle of what looked like parchment, three of them for $7.50. Non-local seafood, like fried shrimp, are just average, though nicely fried and generous. And soups are just fair, the tomatoey crab and vegetable soup slightly better than the thick white clam chowder.

Captain Drinks' serves approximately the same dishes, at prices similar or 20 cents more. But the seafood platter is all painfully overcooked and overbreaded. The fish filet was dry, the softshell crab crumbly, the three scallops and three shrimps rubbery. Three fried oysters had been so imbedded in floury paste that the dough was raw inside though very browned on the surface. Crab cakes were about as heavy as Robertson's, and in addition tasted burned. Captain Drinks' slaw was dry and witlted, but its homemade potato salad was, thankfully, unsweetened. As for soups, could not find any clams in chowder, but we knew there was real crab in the crab soup because half the bowl was shell -- not bits of shell, but whole segments of shell.

What comes free is the entertainment. Wandering along the Popes Creek pier, fishing vicariously. Even the parking lot is a show, the Harley Davidsons equipped with stereos, the unending variety of custom cars and pickups. Popes Creek is the kind of dining neighborhood where little old ladies have their gray hair carefully sprayed into formal curls but wear jogging shoes on their feet. It is one of those places where a man wants his beer belly to hang out, as a badge of honor. The pier's crab houses are not exactly unspoiled; like New Orleans, they feature rotund glasses of fake red juice with rum and the glass to take home as a souvenir. And on Sunday you may need to pack a sandwich for the wait. But, like buying lobster steamed in sea water at a Maine lobster pound and eating it on the hood of your car in the parking lot, some foods need their natural environment in order to develop every nuance of their flavor. And Maryland blue crabs need brown butcher paper, wooden mallets, glitzy juke boxes, pleated paper cups on vinegar bottles and shellacked pine booths in full view of Maryland or Virginia shoreline. Popes Creek has all the requirements, in duplicate.