From www.wdwinfo.com

Universal's Hogwarts Express sees one million riders
Aug 11, 2014

Since Universal Orlando opened the Diagon Alley area as an expansion to their Wizarding World of Harry Potter, one million visitors have already ridden the Hogwarts Express. The train transports guests between Diagon Alley in Islands of Adventure and Hogsmeade in Universal Studios and has only been open since July 8. On Thursday, August 7, complimentary Butterbeer ice cream was passed out to 200 guests to celebrate the one millionth rider. Guests must have a park-to-park ticket in order to ride the train.