Police and fire rescue were called to the Bishop Claggett Center off Buckeystown Pike, where Upward Enterprises, Inc., a ropes challenge course company, operates.
Officials say two zip liners were on a course, when they collided. The impact, in which the injured man's head made contact with another man's shoulder, left him unconscious.
"When they collided the gentleman hit his head on the other gentleman's shoulder. He was not injured so he didn't require any attention so our main focus was on the unconscious individual adult male," said Lt. Jeff Shippey, with the Frederick County Division of Fire and Rescue Services.
The course is in a wooded area which made it challenging for first responders to transport the injured man.
"We were able to utilize the Maryland State Police helicopter to do a hoist, in which they send a line down and we were able to pick him up and take him directly out of the woods," said Shippey.
A representative with Upward Enterprises could not be reached.
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