Kingda Ka is a hydraulically-launched steel roller coaster located at Six Flags Great Adventure in Jackson, New Jersey, United States. Manufactured by Intamin and designed by Werner Stengel, Kingda Ka opened as the tallest and fastest roller coaster in the world on May 21, 2005, surpassing Top Thrill Dragster.

As of 2026, the state with the tallest roller coaster is Texas. This title was recently claimed by Tormenta Rampaging Run, which opened at Six Flags Over Texas in Arlington for the park's 65th anniversary season. Standing at a staggering 309 feet tall, it is classified as the world's first "Giga Dive Coaster," featuring a massive 95-degree beyond-vertical drop. For many years prior, the title of "tallest" was held by Kingda Ka in New Jersey (456 feet), but that ride's status has been subject to change due to long-term closures and decommissioning rumors in the mid-2020s. Another major contender is Top Thrill 2 in Ohio, which reaches 420 feet but uses a multi-pass spike rather than a traditional lift hill. In the category of "traditional" lift-hill coasters that are currently operational and open to the public in 2026, the new Texas giant is the focal point of the industry. These massive structures require specialized engineering to withstand high wind loads and utilize complex chain or cable systems to pull the heavy trains to the summit before releasing them into a record-breaking plunge.