Aside from the new Gringotts ride, the Hogwarts Express is the other big feature of the new land. In fact, several of the actors who attended the preview for the park noted that it was one of the most immersive elements to Diagon Alley. It begins with a walk through the wall onto Platform 9 3/4, a really cool component to the queue for the ride. Boarding the train is like stepping into the films, as every little detail is accounted for. Even the fabric for the seats is the exact same fabric used on screen. Once seated in your cabin, you watch scenes on a 3D video screen window that takes you from London to Hogwarts, and you watch a completely different one on the way back. On the other side, you hear and see the shadows of characters from the series, like the candy-cart lady, the lead trio, and the especially creepy Dementors.
Source: 2014 Universal Orlando Resort