<P> Construction of Diamondback began on October 11, 2007, with the removal of a tree . Swan Lake was drained and filled with concrete before opening day in 2008; this turned out to be the location for the splashdown element . Kings Island started teasing visitors during the Fourth of July weekend in 2008 with signs saying, "Ride sally ride" and "Steep incline ahead ." Diamondback was announced on August 6, 2008 as the largest investment in Kings Island history . The ride was topped off with the 230 feet (70 m) lift hill on October 30 . The last piece of track was installed on January 26, 2009 . Diamondback started testing about a month later on February 26 . Diamondback officially opened on April 18, 2009 . The 1,000,000 th rider was on July 20, 2009 . On July 21, 2014, Diamondback gave its 10,000,000 th ride . The rider, Mike Brogan, was given a Diamondback gift package including T - shirts, hats, keychains, coffee mugs, shotglasses, and a large sign proclaiming his ride . </P> <P> On February 3, 2009, Kings Island announced they would hold an auction for the first riders on Diamondback . The winners of the auction would be given a commemorative first rider ticket, a special gift from the park, and an admission ticket . All proceeds from the auction would go to A Kid Again non-profit organization, formerly known as Adventures for Wish Kids . The first rider auction raised $102,000 . The first eight trains, or the first 256 seats were auctioned off . The average bid was $398 per seat . </P> <P> After the train leaves the station, it begins its ascent up the 230 feet (70 m) chain lift hill . Once reaching the top of the hill, the coaster drops 215 feet (66 m) at 74 ° over the Rivertown midway reaching speeds up to 80 miles per hour (130 km / h). It then curves to the right up a 193 feet (59 m) hill and down the drop into the ravine, curving again to the left . The ride then ascends a 131 feet (40 m) camelback hill and drops, curving left into the hammerhead turn . After dropping out of the hammerhead, the train travels up a 129 feet (39 m) hill (which has a trim brake). After the fourth hill, the train turns down into a 287 ° counter-clockwise helix (on - ride photo camera is here) and into the mid-course brake run . After the short brake run the train drops down into the ravine, raising into a bunny hop hill, then into another bunny hop and into the final clockwise helix of 323 ° . After the final helix, the train passes over the Rivertown midway a second time and drops into the splashdown finale, slowing the train down and leading it into the final brake run . After braking, the train takes a left U-turn and heads back into the station . One cycle of the ride lasts about 3 minutes . </P> <P> Diamondback is the first hyper coaster to feature a splashdown . Scoops positioned at the back sides of the last car on each train send water soaring at heights of 50 ft (15 m) as the train passes . The riders don't actually get wet in the splashdown . Splashdowns are used for a visual effect as well to slow the train down . The splashdown is located in the former Swan Boat pond . </P>

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