As I approached the entrance of the new Six Flags America for the first time, I caught a glimpse of the thrills ahead: The steel tracks of a fiendish roller coaster gleamed just beyond the trees along Central Avenue. The next sight, however, was less than exhilarating. The park is a mere 15 minutes from my home, but I spent a good half-hour staring at the rear bumper of the car in front of me as I slowly made my way past the front gate and into the parking lot.

Six Flags has at least one thing in common with Two-Face, the Batman character and namesake of its new suspended roller coaster. Just like the arch-villian with a split personality, the park displays a smooth side and a rough side. But unlike Two-Face, Six Flags America is well on its way to redemption.

The transformation of the former Adventure World adds a new twist to the local theme park scene. It has undergone a $40 million renovation since its owner, Premier Parks Inc., purchased the Six Flags chain last year and made Largo's Adventure World part of its amusement park empire. It seemed like a dream come true for local theme park enthusiasts: A Six Flags in the heart of Prince George's County. No more one-hour-plus drives to enjoy world-class roller coasters. Anticipation was high as the May grand opening drew near, promising a spiffy new front gate and main street, two new steel roller coasters, a bigger and more elaborate children's area, and more.

At least that was the plan. The opening was delayed a week to apply some "finishing touches," like stocking store shelves and pouring concrete in a few new areas. Then too much success overwhelmed the park when opening day attracted a crowd three times as big as expected.

Traffic and parking problems plagued the area on subsequent weekends. Maybe Six Flags America is more like the Riddler, posing questions without easy answers: Are the thrill rides and other new features worth the hassle of getting into the park? Will the troubles linger throughout the summer? And, that drive to Kings Dominion really wasn't that bad after all, was it?

"When you're just opening something, you can get caught short very easily," said John Schumacher, an amusement park consultant based in Sun City, Ariz. A former director of business affairs for a now-defunct theme park in Indiana, Schumacher has plenty of experience with trying to prepare for the unexpected. "You can do every feasibility study in the world, and there will still be exceptions." He says the true test for Six Flags America will be how quickly it can turn around its iffy first impression. "The most important place in a park is that entry point," he explains. Theme parks offer rides, food and other amenities, he says. "But that first point of access to the park, when [visitors] leave the public road and enter the parking lot, is very important in establishing the mood for the day."

Six Flags managers moved in late May to unsnarl the tie-ups. A second entrance was opened along Route 214 (Central Avenue) and more than 2,400 parking spaces were added to the existing 5,500.

The changes appear to have eased the problems. Park general manager Janet Porter said state and county agencies were extremely cooperative, and the traffic solutions "worked fabulously." The number of state troopers used to direct traffic has been reduced from 19 to five, and a shuttle service that had been offered to transport guests from overflow parking at nearby USAirways Arena has been discontinued because overflow parking is no longer needed, according to Porter.

(Visitors can also use public transportation to get to the park. By subway, take Metro's Blue line to the Addison Road station and catch a C21 bus to the park.)

So what's beyond the parking lot and the turnstyles? The refurbished entrance leads guests to Main Street 1776, an inviting, vibrant strip of gift shops and eateries set to a Colonial theme and featuring Warner Bros. and DC Comics merchandise and characters. From Main Street, take a sharp left to cool off at a popular holdover: Paradise Island, a water park that features water slides, inner-tube rides, a humongous wave pool and supervised children's play areas -- all at no extra charge.

Revisit some other old favorites like the Mind Eraser steel roller coaster; ROAR, the mammoth wooden roller coaster added in 1998; and the Wild One, an older wooden coaster that got a $1 million makeover this season -- and it was a spectacularly underrated ride before! (Have I mentioned that I'm a roller coaster fan?)

If you have little ones in tow, you'll spend a lot of time in the new children's area, Looney Tunes Movie Town. Tykes can explore 12 new rides, many of them miniature versions of adult rides elsewhere in the park. Sylvester's Pounce and Bounce is a tiny (and tamer) Tower of Terror, and the Great Chase gives kids their very own steel roller coaster, with the Road Runner and Wile E. Coyote along for the ride. And the Looney Tunes Studio Prop House is sure to be popular -- it's a Discovery Zone-like play area that appears to have been designed by Daffy Duck.

This section is advertised as being aimed at kids 54 inches and shorter. How much shorter? "If they're able to walk, they're able to ride," said general manager Porter, adding that if a child can sit up by himself, he can enjoy most of the rides in this section. Movie Town also features a kid-friendly musical revue -- and an opportunity for parents to rest their weary feet.

Then move on to the Gotham City section, where the "Batman Thrill Spectacular," a new stunt show, awaits. Five- to 9-year-olds will probably enjoy this program the most. (Some of the special effects might frighten toddlers.) Kids can pose for pictures with Batman and other characters after the show. (At about 20 minutes, this show provides another welcome chance to rest your feet.)

The real draws at Six Flags America are the Joker's Jinx and Two-Face: The Flip Side -- two sensational new steel roller coasters. (Prepare yourself for long lines and waits of 45 minutes or more on weekend days. Unless you arrive the moment the park opens, long lines will be unavoidable at popular rides.)

For my money, they were worth waiting for. The Joker's Jinx is a compact spaghetti bowl of track that rockets riders from 0-60 in just over three seconds. That's 4 G's of force. Space shuttle astronauts feel 3 G's during liftoff.

This purple-and-green tangle is the only roller coaster that ever made me feel dizzy afterward, in a non-sickening kind of way. I've been wobbly and disoriented, but never downright dizzy. The ride requires removal of earrings and eyeglasses. Even with something to hold your glasses on (like Croakies), it's best to remove them because the ride's well-padded restraint makes wearing glasses uncomfortable. (See box at right for more theme park tips.)

The Jinx -- which contorts 2,705 feet of track into 30 vertical curves, 25 horizontal curves and four loops -- was designed to create "a sense of being very out of control, while technically knowing you're in safe hands," said Jim Seay, president of Premier Rides, the Millersville, Md., company that built it.

My riding companion (and godson), Dalantae "Born to Ride" Caldwell, says the Joker's Jinx is fun and "intense!"

"It doesn't gradually get fast," he says, "it goes ZOOM!"

Dalantae, a roller coaster maniac from Fort Washington, is an expert on area amusement parks (as much as a 10-year-old can be). He knew the layout of Adventure World by heart, doesn't need a map to navigate the Virginia theme parks and can name all 10 roller coasters at Kings Dominion off the top of his head.

But he had never ridden anything quite like Six Flags' Two-Face. The ride is only 90 seconds long, but it's a uniquely twisted minute and a half. Riders are seated face-to-face, pulled up a 137-foot lift, dropped down at 55 mph and shot into a "boomerang" double-inverted sidewinder. Then they get to do it all over again -- backwards.

The change in direction and ability to look "terror" in the face are what sold Dalantae on this ride. "You don't get that on other roller coasters," he says.

Sam Marks, a 41-year-old thrill-ride aficionado, is more than a little enthusiastic about Six Flags America. "If this is the beginning, what can the future bring?" asks Marks, a member of the Coaster Zombies, a group of roller coaster fanatics based in Arlington. He raved about Joker's Jinx and Two-Face and looks forward to more envelope-pushing rides. "This is where it's all going to happen," he predicts, looking at the park from a "we live to ride" perspective.

THE COMPETITION

What could compare with this up-and-coming park? How about the tried-and-true at Kings Dominion and Busch Gardens? They still have a lot to offer and are worth the long drives.

Kings Dominion has expanded its old water park, Hurricane Reef, into a resort-style venue and renamed it WaterWorks (included in the admission price). The area now features 2,000 lounge chairs, a huge wave pool, a kiddie pool with ever-present lifeguards and Surf City Splash House, kind of a drenched jungle gym that dumps a 40-foot-high bucket (800 gallons) of water on splash-happy patrons every eight minutes. On scorching summer days, "water park" sections at theme parks can get very crowded very early. This expansion could eliminate the need to stake out a comfortable spot at the crack of dawn.

The park also added "Nicktoons Rockin' Countdown," an interactive live show, to one of its children's sections, Nickelodeon Splat City. And in August of last year, Kings Dominion unveiled Volcano, the Blast Coaster, the world's fastest suspended roller coaster and the park's 10th coaster. Like Joker's Jinx, this one gets off to an explosive start. "Hold your head back," Dalantae warned before the ride shot off. But 5 G's of force took care of that, as the ride quickly reached its top speed of 70 mph, whisked passengers through a mountain, thrust them through the mouth of the "volcano" and zipped through four inversions before returning to the starting point.

Despite the competition the park in Largo poses, Betsy Moss, Kings Dominion's public relations manager, has a collegial attitude and said she wasn't gloating about Six Flags' growing pains. "We're all in the hospitality business," she said. "Making customers happy is what's most important to everyone in the industry." (Kings Dominion honored tickets purchased for Six Flags' postponed opening day.)

Busch Gardens' big new thing is Apollo's Chariot, which left me breathless during its 210-foot first drop (and left romance novel coverboy Fabio with a bruised face after a collision with a goose during a photo opportunity in March). Chariot riders experience a sense of weightlessness, reach a top speed of 73 mph and feel 4.1 G's of force (for those of you keeping track). The park's beautifully landscaped, old-world setting belies some wicked rides, including Alpengeist (which Dalantae claims is the world's most inverted roller coaster), the Big Bad Wolf and the Loch Ness Monster.

Meanwhile, up north, off the New Jersey Turnpike, Six Flags Great Adventure just got a $42 million face lift of its own. And Hershey Park and Sesame Place, both in Pennsylvania, have added new features as well. (See details below.)

The battle for your family's entertainment dollar has grown more fierce. But the bottom line is: Thrill-seekers have more options now than ever.

If your experience at one park is disappointing, you don't have to turn the other cheek. Competing parks beckon, and they all have something distinct to offer. What do you value most? A short drive? Cutting-edge rides? A variety of roller coasters? A picturesque setting? It's all out there, and the choice is yours ... may the G-forces be with you.

PARK AND RIDE

Parking costs extra at all of the following theme parks. Most charge $6 per car per day. Some sites offer parking discounts for season pass-holders. And some sell season parking passes.

If you read the fine print and pay attention to advertisements, you can shave a few dollars off of the price of admission as well. The parks offer a wide variety of discounts, including coupons that are available at area stores and restaurants. Many also have "sunset" or "twilight" prices that lower the cost if you arrive at the park after a certain hour. Some of the best bargains are listed below. Call the parks for details.

MARYLAND

SIX FLAGS AMERICA -- Largo, on Route 214 five miles east of the Beltway. 301/249-1500. Web site: www.sixflags.com

The 135-acre park (described in detail above) is open daily through Sept. 6. Open for "HallowScream" every Friday, Saturday and Sunday Oct. 1-17 and nightly Oct. 21-31. Opens at 10:30 a.m. most days. Closing times range from 6 to 10 p.m. Water park closes at 7 p.m. on Sundays. Call to verify hours. Admission is $29.99, $19.99 for seniors 62 and older and the disabled, $14.99 for children 48 inches and shorter, plus tax (3 and younger free). Additional charge for rock-climbing and Go-Karts. Bargains: Previously purchased season passes allow unlimited admission to all 13 Six Flags parks throughout the country. (These passes are no longer available for purchase this season.)

VIRGINIA

BUSCH GARDENS -- Three miles east of Williamsburg, Va. Drive time is about three hours from the Capital Beltway. 800/772-8886 or 757/253-3350. Web site: www.buschgardens.com

This 100-acre park features more than 40 rides and attractions nestled in a 17th-century European-style setting. New this year: Apollo's Chariot, a "hypercoaster" that takes riders 210 feet up into the air -- and then plunges them back down. And if that isn't scary enough, "Howl-O-Scream" debuts Oct. 15 with a haunted haus and haunted train, a monster-size maze, a laser show and other "spooky" activities. The park is open daily through Sept. 5, Friday-Monday Sept. 6 through Oct. 31. Opens at 10 a.m. daily. Closing times range from 6 to 11 p.m. Call to verify hours. Admission is $35, $28 for children ages 3-6 (2 and younger free), $32 for seniors 55 and older. Bargains: Individual season passes are $93.95, $73.95 for children 3-6. Individual EuroSplash season passes (valid for Busch Gardens and Water Country USA) are $125.95, $105.95 for children 3-6. Virginia Theme Park Vacation packages allow unlimited admission for five consecutive days to Busch Gardens, Water Country USA and Kings Dominion for $110.95 per person. Vacation package deals that include hotel accommodations are also available; call 800/832-1127 for details. The park also offers two- and three-day tickets and military discounts.

KINGS DOMINION -- Doswell, Va. Drive time is about 1 1/2 hours from the Beltway. 804/876-5000. Web site: www.pkdthrills.com

Ten roller coasters wind throughout this 400-acre park near Richmond, including Volcano, the Blast Coaster. New this year: WaterWorks, a 16-acre water park (included in admission) with a 650,000-gallon wave pool and a water-powered fun house; and Nicktoons Rockin' Countdown, where Nicktoon characters celebrate New Year's Eve all summer long with a stage show that features audience participation in "Slime Square." The park is open daily through Sept. 6, weekends Sept. 11 through Oct. 3. Park opens at 10 a.m. on Saturdays, at 10:30 all other days. Closing times range from 8 to 10 p.m. Call to verify hours. Admission is $33.99 for ages 7 through 54, $28.99 for seniors, $24.99 for children 3-6 or under 48 inches tall (younger free). Additional charge for some special events, Xtreme SkyFlyer and climbing wall. Bargains: Individual season passes are $89.99; four family passes are $274.99. Season passes also admit you to four other Paramount parks -- in Charlotte, N.C; Santa Clara, Calif.; Cincinnati; and Toronto. Virginia Theme Park Vacation packages allow unlimited admission for five consecutive days to Busch Gardens, Water Country USA and Kings Dominion for $110.95 per person. Vacation package deals that include hotel accommodations are also available; call 800/832-1127 for details. Two-day tickets are also available.

WATER COUNTRY USA -- Three miles west of Williamsburg, Va. Drive time is about three hours. 800/772-8886 or 757/253-3350. Web site: www.watercountryusa.com

This enormous family water park, set to a '50s and '60s theme, has opened for its 15th year. (It's owned by Anheuser-Busch, the same company that owns Busch Gardens, but charges a separate admission price.) New this year: A children's musical show called "Jump, Jive and --

Duck." Park is open daily through Sept. 6, Saturdays and Sunday only Sept. 11-19. Opens at 10. Closing times vary from 6 to 8 p.m. Call to verify hours. Admission is $27, $19.50 for children 3-6 (2 and younger free), $24.30 for seniors 55 and older. Bargains: Individual season passes are $93.95, $73.95 for children 3-6. Individual EuroSplash season passes (valid for Busch Gardens and Water Country USA) are $125.95, $105.95 for children 3-6. Virginia Theme Park Vacation packages allow unlimited admission for five consecutive days to Busch Gardens, Water Country USA and Kings Dominion for $110.95 per person. Vacation package deals that include hotel accommodations are also available; call 800/832-1127 for details. The park also offers two- and three-day tickets and military discounts.

PENNSYLVANIA

HERSHEYPARK -- Hershey, Pa. Drive time is about 2 1/2 hours. 800/437-7439. Web site: www.800hershey.com

This 110-acre, 93-year-old park features seven roller coasters -- including last year's addition, Great Bear (Pennsylvania's only only steel inverted roller coaster); ZooAmerica, a wildlife park that's included in the admission price; and dozens of other attractions. New this year: Hersheypark Fair, "The fair that lasts all summer long," an area designed to be reminiscent of an old-fashioned county or state fair. The Fair features a 10,000 square-foot exhibition tent and five new rides, including the Wild Mouse roller coaster. Hersheypark is open daily through Sept. 6, Saturdays and Sundays only Sept. 11-19. Gates open at 10 a.m. Closing times vary from 6 to 11 p.m. Call to verify hours. Admission is $30.95, $16.95 for ages 3-8 and seniors 55 and older (2 and younger free). Bargains: Individual season passes are $90.95, $80.95 for ages 3-8 and seniors. Two- and three-day passes are also available; call for details.

SESAME PLACE -- Langhorne, Pa. Drive time is about 3 1/2 hours. 215/752-7070. Web site: www.sesameplace.com

Last year this 14-acre tyke-oriented interactive park, which aims to capture the spirit of PBS's "Sesame Street," added Vapor Trail, a roller coaster designed to entertain the entire family. New this year: "Pet Pals," a live show starring dogs, cats, birds, rats, parrots and pigs rescued from animal shelters. And in "David Jack's Jungle Adventure," the recording artist entertains with songs while helping a lost friend find his way home. The park is open daily through Sept. 7, weekends only Sept. 11-Oct. 24. Opens at 10 a.m. most days. Closing times vary from 5 to 8 p.m. Call to verify hours. Admission is $29.95 (younger than 2 free), $26.95 for seniors 55 and older. Bargains: Individual season passes are $89.95, $79.95 for seniors. Two-day tickets are $43.90. AAA discounts available.

NEW JERSEY

SIX FLAGS GREAT ADVENTURE -- Jackson, N.J. Drive time is about four hours. 732/928-1821. Web site: www.sixflags.com

This 26-year-old park recently underwent a $42 million expansion, adding 25 rides, four stage shows and a new children's section. Wild Safari animal park is still going strong. New this year: The most ballyhooed addition is Medusa, billed as "the world's first floorless roller coaster." Park is open daily through Sept. 6, Saturdays and Sundays only Sept. 11-26, and Friday Saturdays and Sundays Oct. 1-31. Also open Sept. 20 and Oct. 11. Usually opens at 10 a.m. Closing times vary from 6 to 11 p.m. Call to verify hours. Admission is $38.15 for theme park only, $41.34 for amusement park and Wild Safari; $19.08 and $20.67 for children 48 inches and shorter (age 3 and younger free); $20.15 and $23.30 for seniors 55 and older; $15.90 for tickets to Wild Safari only. Bargains: Individual season passes are $84.75. Family season passes (for up to four people) are $291.50. "Twickets" enable ticket-buyers to return for a second day (through Sept. 26) for an additional $13. Call park for details.

THEME PARK SURVIVAL TIPS:

* To avoid the longest lines, arrive when the park opens.

* Take a moment to peruse the map you were handed when you entered the park, plot a general course for the day and note the locations of restrooms and eateries.

* Consider going to an indoor show during the hottest part of the day. They're great places to rest and cool off.

* Pick a spot to meet if anyone gets separated from your group. Most parks have a facility for "lost parents."

* Wear light, cotton clothing and cheap, comfy sneakers. You'll appreciate these when you get soaked on water rides.

* Bring some large, sealable plastic bags to protect your wallet, etc., during aforementioned water rides.

* Head for the water rides early so you can dry in the sun throughout the day and avoid a soggy ride home.

* Don't forget to slather on plenty of waterproof sunscreen.

* For people who wear prescription eyeglasses, bring "Croakies" for most thrill rides.

* Carry a fanny pack or drag along a person who hates thrill rides and doesn't mind holding your loose items while you ride. Cubby holes are available at most thrill rides, but it's easier (and more secure) to travel light. (Unfortunately, the new coasters at Six Flags America don't offer cubby holes.)

* Pay attention to the height requirements for the popular thrill rides. It's frustrating for a child to wait in line for 40 minutes only to be told she's too short to get on. Six Flags measures kids after they wend their way through the lines, while Kings Dominion has a one-time measurement station near the entrance to the park.

* Heed the warning signs posted at thrill-ride entrances. They recommend that pregnant women and people with neck or back injuries, recent surgery or illness, heart trouble or high blood pressure avoid these rides. As a friend with neck problems recently learned, this can be a painful mistake.

* If you can't stand waiting an hour or more to ride THE BIG NEW STATE-OF-THE-ART, HYPED-TO-THE-MAX RIDE at the park of your choice, turn to an old reliable alternative. For example, there's often a short line at Kings Dominion's Rebel Yell. You could ride the old wooden coaster five times while others are waiting for one vault through Volcano. And the Rebel Yell is still a blast!

CAPTION: Heads or tails? Riders will flip for Six Flags America's Two-Face.

CAPTION: Busch Gardens' Alpengeist, named for a ghost that haunts the Alps, takes passengers on a chilling ride.

CAPTION: Kings Dominion's Volcano blasts riders through four inversions.

CAPTION: Bathing cuties at Surf City Splash House in Kings Dominion's new WaterWorks.