American Coaster Enthusiasts. The name says it all. American Coaster Enthusiasts has more than 5,500 members who go cuckoo for coasters. A favorite event among ACE devotees is Exclusive Ride Time—a few hours that parks set aside before opening or after closing for ACE members to enjoy the coasters crowd-free.

The European Coaster Club. Coaster enthusiasm is not limited to the U.S. Thrill seekers join the European Coaster Club to participate in regularly scheduled member trips with like-minded folks daring to test the laws of physics. The group boasts more than 1,500 members and says a few romances have even blossomed as couples looped the loop.

International Association of Amusement Parks and Attractions. The International Association of Amusement Parks and Attractions is the trade association for “permanently situated amusement facilities,” which are home to most major coasters around the world. The group strives to help members improve efficiency, marketing, safety, and profitability.

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