Definitely...But prior to Hogwart's Express, that wasn't really the case. Even now, you really need to tour commando, and basically miss all the entertainment venues and the ambiance of the park, to do both parks in one day. It really takes two days minimum now, especially if you spend any kind of satisfaction time in Diagon & Hogsmeade.....The great thing about HE is that it makes it easier, plus a really good attraction (and under rated by some) , to travel between the two parks....Even someone like me, that takes long Universal vacations, before HE I rarely did both parks in the same day, even though they're a fairly short walk between them. Since HE, I'll usually travel between the parks more than once a day. Now I rarely just spend time in one park. HE made a monumental move in touring habits. It's really jst One Big Park now...Hogwarts Express was pure genius.