Yes, you can go to both Disneyland Park and Disney California Adventure with a Magic Key, but the "how" depends on your Park Hopper privileges and the current reservation rules for 2026. All Magic Key tiers (Inspire, Believe, Enchanted, and Imagine) include Park Hopping as a standard feature. When you make your mandatory theme park reservation, you choose your "starting park." Once you have entered that first park, you are permitted to "hop" over to the second park anytime after 11:00 AM (though this time is subject to change based on Disney's operational needs). You do not need a second reservation for the second park. However, park hopping is always subject to capacity limits; if a park is completely full, Disney may temporarily pause hopping to that location. For Magic Key holders, this flexibility is a major benefit, allowing you to start your morning with a ride on Space Mountain in Disneyland and end your evening with World of Color in California Adventure. Just remember that you must enter your first reserved park before you can hop to the other, even if it is after 11:00 AM, to "validate" your reservation for the day and avoid a "no-show" penalty on your account.