Once a year, members of the American Coaster Enthusiasts, aka “Coaster Crazies,” descend on an amusement park to immerse themselves in their passion, riding roller coasters. This year, they picked Six Flags Over Georgia and its 10 roller coasters. ACE members Bill Beatty, 78, of Ft. Lauderdale, Fla., and Lucy White, 88, of Savannah, Ga., ride Superman: Ultimate Flight.

ATLANTA — Hours before the first funnel cake was fried and the biggest stuffed panda was won, more than 200 people waited patiently outside the turnstiles at Six Flags Over Georgia.

Two hours before the park opened to the public, they were ready to ride, with sensible shoes, fanny packs and no loose objects in their pockets. As members of American Coaster Enthusiasts, a group 7,000 strong, they’re dedicated to knowing, loving, preserving and testing every coaster out there.

“We also call them ‘Coaster Crazies,’” Six Flags’ spokeswoman Hela Sheth says with a straight face.

For the group’s annual Coaster Con this week, its members pilgrimaged to Six Flags and Wild Adventures in Valdosta, Ga., for “exclusive ride time,” or ERTs, that open the park early and keep it operating late, just for them. Some extended their ride time with trips to parks in Alabama and Tennessee. About 500 enthusiasts live in the Southeast, and some acted as guides to the riders visiting from California, Pennsylvania, Arizona, Washington, Canada — even Norway.

“When ACE started in 1978,” says Robert Ulrich, 54, an enthusiast and ACE regional rep from Marietta, Ga., “nobody knew there was somebody like them.”

“Like them” means thrill-seeking, ride-critical, community-oriented history buffs. The earliest members joined by writing in for more information; now people can sign up online, sometimes as a family, if their stomachs are strong enough.

There are 2,080 coasters operating in the world today; some members have gotten to more than 1,500 of them. They try to save the old ones, and obsessively track their histories. Ask them to name a favorite, and the universal and diplomatic answer is, “Whichever one I’m riding.”

But they do have favorites.

They know the manufacturers and designers, and which parks have the best view from the top. ACE president Mark Cole, who lives in Florida, admits that he loves the Incredible Hulk coaster at Universal’s Islands of Adventure in Orlando, his home park. His favorite wooden coaster is Phoenix, a ride at Knoebels Amusement Resort in Pennsylvania.

On Six Flags’ Ninja just before 9 a.m., Cole doesn’t scream or throw his hands in the air. The ride is a nice way to wake up, but he’s more excited about Mind Bender, the Georgia Scorcher and the Georgia Cyclone.

“This is what I’d call a cookie-cutter ride,” he says after Ninja’s brisk minute-and-half at 52 miles per hour, upside down. “It’s fun, it’s smooth, but it’s just like others around the country.”

After their fourth fly on Superman, which kicks its riders forward so they can soar face down at 60 mph, Jayson Young, 32, of Virginia, and his sister, Melissa Young, 34, of Connecticut, gush.

It’s better than the one in New Jersey, they agree, but nothing compared to their favorite at Six Flags Over Georgia, Goliath. (ACErs adore that 20-story, 70 mph ride — it transforms coaster-haters into coaster-lovers.)

The Youngs have brought Melissa’s son James, 12, to Coaster Con from the time he was in a stroller. His favorite is Maverick, a new coaster at Ohio’s Cedar Point.

They’re not screamers, James says. They “pretend panic,” to work up other riders. “We’re just playing around,” James says. “We’re laughing at them.”

Some enthusiasts love to yell, ACErs like Bill Beatty, of Ft. Lauderdale, Fla., and Lucy White, of Savannah, Ga. They are front-car, hands-up kind of riders. Others defer to them, the king and queen of coasters. Beatty is 78. White is 88.

He rode his first coaster as a child, maybe 5 or 6. She was a teen in Texas who defied her parents’ fears to catch a ride. It’s been all up and down since then.

They like a nice smooth ride on a steel coaster, but what they really love is the anticipation of the lift hill on a wooden coaster, the oil and lumber smell on a hot summer day, the clink-clink of the climb. White could hardly get to sleep the night before her first morning of “exclusive ride time.”

“The Great American Scream Machine is my favorite,” White proclaims, hailing the lifts and air time. “Up and down, up and down.

“By the third hill,” she jokes, “it feels hum-drum.”