For three days, the IU freshman was trapped in the cave, wondering why the other students had left him behind in the darkness. He licked the moisture off the walls that surrounded him. He licked the wrappers of Clif bars and debated eating crickets. In the dim light of his iPhone, he tapped out goodbye letters to his family. After the battery died, he carried on imaginary conversations with the friends he thought he’d never see again.

“I was very confused and pretty scared,” Lukas Cavar told the Indiana Daily Student. “It took me a little while to wrangle my emotions and sort of approach things analytically, sensibly, to come up with a game plan to survive.”

Cavar, a 19-year-old physics major, was rescued late Tuesday night after the president of the Caving Club realized that the group had forgotten the freshman at the end of Sunday’s trip to Sullivan Cave in Southern Indiana. The club’s leaders raced to the cave and unlocked the entrance gate — the same gate one of them had locked on their way out, trapping Cavar.

“You could tell they were pretty shaken up,” he said. “They did near kill me. I can’t imagine what kind of guilt they felt.”

As soon as the club leaders freed the freshman, he devoured a bowl of pasta and a leftover Big Mac one of the rescuers brought to the scene.

“Probably the best food I’ve had in my life,” he said.

As of Friday, unanswered questions lingered. The club leaders, who asked not to be named, refused to explain exactly how Cavar was left behind.

“It’s a sensitive legal matter," one said.

Caving Club leaders told the IDS they conducted a head count before and after the group of 12 entered and exited the cave. Each caver, they said, was paired with a buddy.

“We have a series of rigorous protocols in place that are supposed to prevent situations like this, but they are only effective if followed,” the club's president wrote in a statement posted on IU beINvolved. “We had a failure in our leadership to closely follow all these safety procedures. The risk that our member was exposed to as a result of these failures is a vivid reminder of why we have protocols.”

Cavar’s disappearance was reported as being Sunday to Tuesday, according to the IU Police Department. The details of his rescue weren’t confirmed until Wednesday, when he posted on Facebook. The story spread around campus the next morning.

“We are extremely relieved that, despite being tired and hungry, the student was found to be safe, calm and in good condition and that he is currently doing well,” IU spokesman Ryan Piurek said.

Cavar learned about Caving Club at IU at August’s involvement fair, and said he thought it would be fun and a good way to meet people. Sunday’s trip to Sullivan Cave was intended for beginners like him, he said. There were 12 people in the group, including 11 students and one staff member. They carpooled from Bloomington and arrived at the cave at 10:30 a.m.

The entrance to the privately owned cave is locked to stop untrained trespassers from entering and getting hurt. The club leader, who had permission to enter, unlocked the gate with a key. He and the others split into two groups of six. At first, Cavar was in the second group.

The two groups explored for nearly three hours. As they began their return, they reached a section of the cave known as the Backbreaker, named because the ceiling is low and people are forced to hunch over as they cross.

“I thought, I’m not really enjoying this backbreaker part,” Cavar said. “So I thought I’ll just see if I could bang it out.”

Cavar decided to hurry so he could meet up with the front group. But he missed the narrow rift in the wall that led towards the cave’s exit. When he realized his mistake, he stopped to avoid confusing himself further and waited for someone to find him. After roughly half an hour, no one was yelling his name or coming back.

With the help of graffiti arrows on the wall, he managed to backtrack until he found the rift and reached the cave’s exit.

“I was basically at the surface, but I was still underground," he said.

By now it was 3 p.m. and the rest of the group had already left, locking the gate behind them.He began searching around the cave and found a paper clip. He used it to saw at the padlock for six hours. But, it was a steel lock, and he wasn’t getting anywhere. He thought it would be better to conserve his energy.

Cavar was dressed in light clothes, knee and elbow pads and hiking boots. He had only a plastic Kroger bag, two chocolate chip Clif bar wrappers, two empty water bottles, his iPhone, wallet and a helmet equipped with a light. He said there was no cell reception. He turned the helmet light onto flashing and placed it outside the bars of the gate.

He could hear cars passing on a nearby road and began to yell.

“Help,” he said he repeated for six to eight hours. “Is anyone out there?”

As that first day wore on, he panicked. He tried to figure out what would keep him going. He said it was his friends and family he kept in mind.

“I’d like see them again, so I think I’ll just keep surviving ‘till they find me,” he said. “They’re bound to eventually stumble upon me, right?”

As it got dark outside, he realized he’d have to prepare for a night in the cave. Bats flew in through the locked gate. Cavar feared he would be bitten and get rabies, so he moved in deeper in the cave to be further from the bats, but it was colder there. On his iPhone, he began writing goodbye letters to his family.

The second day, Monday, thirst and hunger overwhelmed him. He longed for chicken lo mein, maybe from Chow Bar or LongFei.

“There wasn’t that much going on in my head, which is kind of nice on some level,” he said. “I’d rather deal with physical pain than existential fear.”

Monday night his phone battery died. He began to have pretend conversations with his family and friends about what he was going through.When he got cold, he made himself walk around.

By now he was so thirsty, he spent hours licking the walls of the cave for moisture. He even bottled his own urine, Bear Grylls-style. But it was too cold and too humid to recycle the urine into something drinkable. Even so, it helped to occupy his mind.

“It gave me hope to experiment with stuff like that,” Cavar said.

The third day — Tuesday now — was the roughest, he said. The cold was wearing him down. He considered eating the cave crickets. He curled into a fetal position and waited.

At some point, he thought he saw a light. He wasn’t sure if he was dreaming. He’d forgotten where he was. When he realized the light was real, he scrambled to the locked gate.

On the other side, he saw one of the club’s leaders approaching with the key. The leader, a certified EMT, performed a routine medical exam. He asked Cavar to say his name, where he was, the time of year.

“The guy who locked me in the cave, who actually physically turned the lock, was the same guy who unlocked the cave and got me out, three days and three nights later,” Cavar said.

By now it was midnight and other rescuers were arriving. They asked him if he wanted to go to the hospital. He said he wanted to go back to his room at Read Center. The club leaders said they agreed to his request because they said he was of clear state of mind.

One sign that showed he was OK was that before they left the cave, he remembered to carry out his waste from the previous three days. It’s common caving etiquette to remove feces after a trip.

The rescuers offered him a pair of fresh socks and a sweatshirt. They gave him water, the pasta and the Big Mac. Cavar also said they apologized profusely.

One of the leaders said she has been in touch with Cavar a few times since they rescued him. He’s recovering well, she said.

Cavar agreed he’s doing well and is already back to school and work at his job at Herman B Wells library.

The club leaders told the IDS they are working on specific changes to their safety protocols and doing their best to make sure something like this never happens again.

On the caving club’s website they still list their 10 safety guidelines. Number four is never go caving alone.

“Solo caving is dangerous,” it reads. “If you were hurt there would be no one to go for help.”

This story has been updated.

Correction: An earlier version of this story reported IUPD was notified of Cavar's disappearance Sunday. The department was notified Tuesday night.

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