Chattanooga-Hamilton County Rescue chief Bob Lewis said two men entered Ellison's Cave on Pigeon Mountain at 7 p.m. Friday, but the situation turned dire on their way back out.
The pair had some caving experience and made it down the first 125-foot pit without a problem, and snaked their way underground to a 586-foot vertical pitch known as Fantastic Pit.
They rappelled down the pit and spent several hours exploring around the bottom, but when they turned around to climb back up at approximately 1 a.m., the Auburn student found he was too exhausted to make it, Lewis said Saturday evening after the climber's successful rescue.
"He just realized there was no way he was going to get out of there on his own," Lewis said.
The climber's situation was complicated by the fact that the first several hundred feet of the ascent were spent climbing through a waterfall and hypothermia was setting in.
His friend, a senior at Mercer University, managed to make it up to his friend and help him rappel back down to the base of the pit while he went on to get help.
Six hours later, at 7 a.m., the initial response team was entered the cave.
They found the man suffering from hypothermia and exhaustion, but after warming him up and putting him in dry clothes, they were able to begin the rescue process and haul him back up to the top of the pit.
As the group left the cave at 12:45 p.m., he was able to walk with some assistance. He was evaluated by Puckett EMS and declined to be taken to the hospital.
"It was all a little more than they could do and they were a little inexperienced," Lewis said. "They were just very lucky."
Lewis said 45 responders from the Walker County Rescue and their cave team, CHCR, and the Department of Natural Resources helped with the rescue operation.