If you're used to getting a park hopper ticket and doing both Disneyland and Disney California Adventure in the same day in the States, you'll be surprised to see that this is discouraged at Tokyo Disney. The only way to get a park hopper is to stay at one of the three Disney resorts. Most people do one park per day — and, in fact, the two-day passport specifies that it's for one park the first day and the other park the following day — especially since there's plenty to see at each park and the lines can get pretty crazy.