Hello, Luisa!
Participating in a runDisney event is absolutely magical! I'm excited to hear you are ready to experience the magic, too. Now the hard part, selecting the right race weekend to be a part of - here are my top choices for Disneyland® Resort & Walt Disney World® Resort runDisney races.
Disneyland® Resort
Disneyland® Half Marathon Weekend is my favorite runDisney event! I love the course and the old-school theming this race seems to pay to classic Disneyland®. The field of runners is also considerably less than Walt Disney World® which will help you from feeling overwhelmed. In addition, if you are staying at a Disneyland® Resort Hotel, the starting line and finishing line are right within walking distance. This means extra sleep! I also prefer the less humid weather that typically occurs in California over Florida.
Walt Disney World® Resort
Disney's Princess Half Marathon Weekend is a fantastic race for families. The royal atmosphere and mostly female runners, make this a great first race - it was my first runDisney event :) Now, if you're looking for a runDisney race experience during a long vacation, Walt Disney World® Resort is, of course, the larger of the two Disney Parks Resorts.
Of course, since you still have plans to visit Walt Disney World® Resort, I would take your first runDisney adventure to Disneyland® Resort.
I hope this helps with your decision, Luisa! Please let me know if you have any additional questions. I am here to help you plan a memorable runDisney-cation at either Disney Park!
Faith