This is what I found out about it... message from the RunDisney people:
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Thank you for contacting us at runDisney.
We appreciate the opportunity to review your inquiry. We have two options for Guests who would like to participate in a running event while onboard. The most popular is the
Castaway Cay 5K, which is open to all
Disney Cruise Line Guests during their voyage. A special medallion is presented to those who finish the race. Once aboard, please see the Port Adventures Desk for more information and registration since Guests are unable to register for the Castaway Cay 5K prior to boarding. An additional option is the Castaway Cay Challenge event. This is a special medal race available for Guests that took part in one of the events from the Walt Disney World Marathon Weekend as well as the Castaway Cay 5K event. You can go to
DisneyCruise.com to book your cruise aboard the Disney Dream today and then register for the Castaway Cay Challenge on
Active.com. Cruises are limited and you will need to book this first before our running event. Both Castaway Cay options provide a fun experience and we are happy to offer them for you to enjoy.
We hope this information is helpful to you in planning to participate in one of our runDisney events.
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