They're the midway at the county fair writ large, larger, largest, carried to the logical illogical extreme and spinning at speeds our grandparents never dreamt of. Yet at bottom, theme parks appeal -- as carnivals and fairs have always done -- to the child in us who wants to be safely scared, goggling at creatures from beyond our ken or whirling gravity-free above the world, daring dizziness to its edge. Here, then, is our annual survey of theme parks within reasonable reach of Washington, in approximate order of driving time. As in years past, the reviews are by Hank Burchard.

There's an almost brand-new amusement park out near Capital Centre, and families with young children may well find it more fun than its famous competitors.

WILD WORLD, which opened late last season in Largo, can be reached by Metrobus. And it's decidedly different.

There are quite a few of the standard sit-there-and-take- it rides and shows, but the emphasis is on participation. And it's the only one of the parks Washingtonians frequent where you can beat the summer heat by getting good and wet on purpose.

Bathing suits are a necessity at Wild World (not to be confused with the animal preserve that once occupied the 600-acre grounds). The centerpiece of its Water Works section is a million-gallon swimming pool, promised to be ready on opening day, that will have four-foot waves and room for 2,000 people at a time, plus space for 6,000 on a two-acre carpeted sundeck. There's also a 10,000-square- foot, 10-inch-deep Tad Pool, with water cannons and stuff.

If surfing isn't vigorous enough, you can go zipping down the Sun Streaker water slide, a 220-foot nearly straight shot that you take from four stories high, sitting only on your bohunkus. Neither are mats used on the four chutes of the Rainbow Zoom, which are less steep, more winding and 400 to 560 feet long. A youngster may ride the two lower and slower ones if a parent has the guts to go along.

There are two special play areas for children. Playport is all soft and non-mechanical devices to climb on, around and through or, in the case of the Ball Bath, to jump into. There's also a maze and what's alleged to be the world's greatest sandpile. Kiddie City has simple games (everybody wins), scaled-down rides and animals to pet.

There's a steam-powered railroad that passes through a hundred-acre exotic animal park; a craft village, cafeterias and snack bars, arcade and video games, midway-type booths and more or less of what we've come to expect in theme parks except for a roller coaster. Plus an elephant ride, which lasts about five minutes and costs a dollar, not hard to understand if you've ever forked hay for an elephant.

The park will cater for groups of 100 or more, offering such amenities as picnic pavilions and playing fields as well as reduced rates.

There's also, surprisingly, a walking trail for those who have had enough of crowds for the moment. It winds by Pleasant Hill Mansion, built around 1720, which is on the National Historic Register; the house needs extensive renovation and isn't open.

This sort of thing is a refreshing change from the public- be-crammed attitude that guides much of the design and operation of parks where the number of patrons processed per hour is not only the bottom line but often the plainly apparent management attitude.

By all accounts, the pace at Wild World is reminiscent of the leisurely golden days of Glen Echo and Marshall Hall. Possibly this is related to the fact that the park is not a subsidiary of a giant corporation but is owned and overseen by four partners who all live in the metropolitan area. It's to be hoped that this laid-back atmosphere can be maintained over a full season (a million visitors are expected in 1983, compared to 400,000 last year).

The new attraction at KINGS DOMINION is White Water Canyon, a float ride along a foaming cataract with bumps and whirls and surprise geysers.

YOU WILL GET WET ON THIS RIDE, the signs promise. And they deliver, by the quart, by the gallon and occasionally by the head-to-toe torrent. Indeed, the chill is the main thrill of the 1,800-foot man- made river, which is less fearsome than it looks.

"We could have made it hairier, but we were looking for something that would be fun for grandchildren and grandparents alike," said park manager T. Lewis Hooper. They found it: The mother of my children, who will not even look at a roller coaster, happily rode White Water Canyon several times; yet it was exciting enough to keep the kids riding it a dozen times before we could tear them away.

The ride lasts four to five minutes, depending on how many times your free-floating boat bumps the walls and pauses in the backflow of the three-foot rapids. The downriver side of the six-seat craft, which is essentially a giant innertube, is the one that gets wettest, and one of the virtues of the bumping and spinning is that the rider who laughed at you last time is likely the one to get deluged next time. If anyone gets through the rapids dry, there are 30-foot geysers strategically stationed to correct that.

There are plastic capes available for the chicken-hearted, but they cost a dollar(!) and anyway you'd need at least two of them, so what the hell. You can always dry out on the park's three roller coasters.

White Water Canyon is said to have cost $3 million -- another sign that Kings Dominion isn't willing to concede first place to Busch Gardens. Much of the money went into landscaping with giant boulders, which has transformed the 10-acre site into a very fair approximation of a rockbound river.

The ride is said to be capable of handling 2,880 people per hour, which one hopes may reduce the waiting time at some of the other attractions. But people who can't stand waiting in lines shouldn't go to amusement parks anyway.

The park now offers 39 major rides, 10 of them child- sized, plus a safari section with a hundred species. In an effort to be all things to all people, the management this year is also offering seven new shows, led by a half-hour musical about -- what else? -- amusement parks. There will also be a number of rock, pop and country concerts, with dates and entertainers to be announced.

And hey, beer lovers, it's all Coors on tap at Kings Dominion now. Take that, Augie Busch.

At HERSHEY PARK you'll find the smallest, least expensive and most charming of the amusement parks within daytrip distance of Washington.

Possibly because the park doesn't stand alone but as part of the Hershey company's generations-old tourist complex, the operators don't seem to feel a frantic need to pull in every possible dollar while the season lasts. Or perhaps it's the Pennsylvania Dutch genius for hospitality. Anyway, the cheerful young people who are always running around the park tidying up and being helpful seem to be smiling because it comes naturally, not just with the job.

And, it being the oldest of the region's theme parks, the landscaping is fully mature, full of attractive places to wander or sit and rest.

Which is not to say hard-chargers can't get as sick and tired as they want at Hershey Park: There are three dozen rides that will spin, loop and twist you to your heart's content or your stomach's contents. Notable among them are the Sooperdooperlooper, Comet and Trailblazer roller coasters, the Pirat swing-boat and the Cyclops, which is sort of a high-speed ferris wheel that gets up and lies down again.

The park's version of an animal preserve is Zooamerica, a walk-through exhibit of 220 species in five representative North American habitats. It covers 10 acres and is open year-round.

Although the park's food quality has been variable, on the whole it tastes better and costs less than at most. Those who like sit-down service may want to try the Tudor Rose Tavern, new this year and offering everything from sandwiches to full-course meals.

In its jolly, hang-the-expense quest for new and better ways to make its patrons sick, BUSCH GARDENS has come up with another winner.

New this season is "Da Vinci's Cradle," a rocking-boat-and-ferris-wheel hybrid that swings 40 passengers, seated in an open gondola, back and forth until they get good and woozy. Then it goes up and over, through 360 degrees (riders always remain right-side-up). Sometimes it goes forward, sometimes backward, and now and then it stops, in a pattern known only to the computer that runs the thing.

"No two rides in a row are the same," said C. Michael Gross, park manager. "It looks pretty tame, but it feels like -- well, I rode the one at Tivoli Gardens in Copenhagen twice, and then I found a bench and let the other people, er, enjoy themselves, if that's the word." It should be enough to gag a maggot.

Unfortunately, the new ride will not increase the elbow room at Busch Gardens, because it's sited in the Italian Village area. The narrow European-style "streets" and small squares, along with the ridge-and-ravine topography, make The Old Country as confining as it is handsome; Busch Gardens on a busy day is no place for claustrophobes.

Smarting from a falloff in attendance growth because of last year's demi-World's Fair in Knoxville, the park is betting its big money this season on a headliner concert series, with such top names as Ray Charles, Waylon Jennings, Merle Haggard and the Statler Brothers. But there's a catch: Last year the park admission included such features at no extra charge, first come, first served; this season patrons must pay $2 to $4 more. On the other hand, concert tickets may be purchased in advance, by mail or at the park, and seating is guaranteed in the Royal Palace Theater, now expanded to 5,200 seats.

The park, which in the past has stressed Old World charm and family gemuetlichkeit in its promotions, will come out swinging in this season's ads. They're aimed squarely at the thrill-and-chill set and damn the demographics that other parks are heeding, which suggest that the kids of the '60s baby boom are settling down to have families of their own.

Other new attractions at Busch Gardens include: L'alliante Piccolo, a "hang glider" for youngsters; Broadway- and country-style musicals; Threadneedle Faire, a medieval games area; and wandering street characters such as Merlin, Shakespeare and Rainmaker.

Jackson, New Jersey, is too far from Washington for daytripping, but a family passing through the area with a day to spare won't be disappointed by GREAT ADVENTURE. The rides and shows are at least equal to anything offered by Busch Gardens and Kings Dominion, and the 51/2-mile drive-through animal preserve is in a class by itself.

There are two -- count 'em two -- major new rides this year, expressly designed for negative-G nuts. FreeFall drops you, caged in a tracked car, from a 110-foot tower, reaching 55 mph in three seconds. Parachuter's Perch, reminiscent of a ride at the 1939 New York World's Fair, hauls you, sitting on a belted swing seat, 250 feet (yes) into the air and then drops you, under cable control, at approximately the rate of a real parachute. It's said that the drop comes as a relief after that long slow haul of 25 stories into the air; just looking at the tower is enough to discourage a sane person.

Other rides include: Roaring Rapids, a float trip redesigned for this season; the interlocking Lightnin' Loops, shuttle roller coasters; Rolling Thunder, a monstrous classic wooden roller coaster; two huge-and-high log flumes, and the Giant Ferris Wheel, sure to bring a nostalgic tear to the eye of any prewar (WWII, that is) patron.

The FreeFall and Parachuter's Perch notwithstanding, Great Adventure is shifting its emphasis from the teen-age set to families with young children. "We hope the new rides will take some of the pressure off the other attractions," a spokesman said. "We're bringing back our wild west show, as well as opening up a bring-your-own picnic area and a big midway, to give families more room and a gentler pace."

The drive-through safari is marvelous, with minimal restraint of the animals. They've had to cage the leopards, though; apparently bored with ready-to-eat meat, they learned to cling to the undersides of vehicles and hitch a ride into the ungulate area. You can stop your car (but not get out, of course))to watch what you like for as long as you like. Sometimes you have to stop, because the animals have the right of way and often cross the road just to cross the road.