The company that runs the event, a subsidiary of Tough Mudder LLC, moved the venue last month to a course about 10 minutes away to Amesbury Sports Park. Then last Friday afternoon, participants received an e-mail that the event had been relocated again, this time to Sunset Ridge in Westbrook, Maine.

The event, called Mudderella, initially was to be held in Kimball Farm in Haverhill.

Some of the roughly 11,000 men and women who signed up to compete in a popular obstacle course challenge are angered about organizers' refusal to give refunds after abruptly moving the event to a site more than an hour away from the original venue.


The first change was made after officials banned events from being held at Kimball Farm because a previous event had created traffic tie-ups, the company said. The second change came after that venue "lost the rights to their property due to pending legal problems."

"Unfortunately, per the no refund agreement signed during registration, we will not be issuing refunds," the event's website said.



Organizers said registrants can transfer for free to participate in another Mudderella event in other cities this year or next year. Events are scheduled this year in Detroit, Virginia, and California. Dates and locations for 2015 Mudderella events have not been set.

"To switch this at this point and then to not allow refunds is just so disheartening," said Nicole Caretta. She said she signed up in April, paying $95.55 for herself and the same amount for a friend .

Lindsay Anthony, a spokeswoman for the event, said in an e-mail to the Globe that organizers have moved quickly to keep the event from being canceled and to notify participants.

The event's course measures between five and seven miles and features 12 to 15 obstacles.

Matt Rocheleau can be reached at matthew.rocheleau @globe.com. Follow him on Twitter @mrochele