By the time Lukas Cavar was rescued from a cave in southern Indiana, the abandoned college freshman had spent nearly three days trapped in its dark confines, fearing he might die there.
To survive, Cavar says he licked the cave walls for moisture and the wrappers of his Clif bars for any trace amounts of food, as first reported by the Indiana Daily Student. He wondered whether he would see his family and friends again, and began typing goodbye notes on his phone - before its battery died on the second day, Cavar said.
The Indiana University student had been exploring Sullivan Cave, about 10 miles south of his school in Bloomington, Ind., on Sunday with other members of the Caving Club, a campus extracurricular group that promotes "responsible caving practices with opportunities to visit caves around the area."
Over several hours, Cavar got separated from the group - and then left behind in the cave after the other club members exited and padlocked the entrance gate.
It would be nearly 60 hours before they realized their mistake and returned to rescue him Tuesday.
"In that sort of situation, if you let your mind wander, it'll go to some pretty bad places," Cavar, 19, told The Washington Post. "I guess that's where I went ... that I'd die alone in this cave."
On Sunday, after he realized he had been forgotten by the group, Cavar spent hours screaming out of the cave's locked entrance - about a 1½-by-3-foot hole in the ground, surrounded by concrete with metal bars welded into place - in the hopes that someone would hear him from a nearby road. No one did.
"The first day I was in very, very bad shape. I was panicking. I was very confused. I really didn't take any time to sit down and think of my situation," Cavar said. "I was pretty sure I wouldn't make it out of that cave at that point."
He told the Associated Press that, with no cellphone reception, he also had attempted unsuccessfully to pick the lock on the entrance with a paper clip. As evening approached on the first day he was trapped, Cavar evaluated the items he had with him, his surroundings and how he could prolong his survival, according to the AP:
Dressed in light clothes, hiking boots and a helmet, Cavar had a plastic bag, two energy bar wrappers, two empty water bottles, a cellphone and a wallet. He used the energy bar wrappers to collect moisture and the water bottles to collect rainfall and puddled cave water.
Cavar also licked the cave's damp walls to quench his thirst. Hunger drove him to consider foraging for cave crickets, although he didn't eat any of the small insects.
Once night came, Cavar took out his phone and started writing down exactly how he got lost at first, his condition, what supplies he had and any other thoughts. As it got darker outside, the cave grew colder.
"Right now I need some rest and thinking. Battery around 56% of phone, and headlamp seems fine so far. Should try to conserve. Good luck me," one note to himself read.
Later, Cavar followed up: "Many salamanders all around. Possible food source? Spiders too, disconcerting. Killed as many as I could find in vicinity. Thinking of family."
Another day went by and he wrote: "Night two is about to begin. Let's hope the temperature change isn't too drastic. Bats and snakes coming out. Feels like Halloween coming early."
Cavar started writing notes on his phone to family and friends in case he died in the cave. He dreamed of people rescuing him.
"3:45- missed all classes today. Surely somebody will have noticed by now," another note read.
Turns out, someone did.
His friends noticed that he missed physics class Monday, which was unlike him, they said. When he didn't show up Tuesday and never went to work that day, they knew something was wrong.
"Lukas is not one to miss class. I don't think he's missed a single class since college has started at all, and we were a little bit worried about that," his friend Sam Norrell, 18, told The Post. "Lukas would never miss work without calling in. He'd have to be very sick not to call work. That was the tipping point."
When Norrell and other friends couldn't find Cavar around campus, they contacted the Caving Club, and that's when they realized that he might still be in the cave. The rescue was a blur for Cavar, but what he does remember is that the club members who found him brought him a Big Mac and a pasta meal - both of which he happily devoured.
He told the Indiana Daily Student that club members apologized.
"You could tell they were pretty shaken up," Cavar told the student newspaper. "They did near kill me. I can't imagine what kind of guilt they felt."
His friends, including Norrell, were waiting at his dorm when he got back.
"We hugged him and we were sobbing," his friend Maris Pilgrim, 19, told The Post, adding that they made him some pizza rolls and helped him get the dirt off his face.
They stayed up until the early hours of Wednesday morning as Cavar told them of his experiences inside the cave. He resumed classes Thursday and has since started rabies shots.
Cavar wasn't reported missing to campus police until Tuesday, officials said.
"We didn't get involved in this until he had actually been let out of the cave," Craig Munroe, captain of the Indiana University Police Department, told The Post. "We were notified by residence staff."
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Indiana University spokesman Ryan Piurek confirmed to The Post that Cavar was left in the cave from about 2 p.m. Sunday to midnight Tuesday, when he was rescued.
"We were extremely relieved that this brave and resourceful student, aside from being tired and hungry, was found at the entrance to the cave unharmed, composed and in good condition, and that he is currently doing very well," Piurek said in an email. "Considering the scary circumstances, it was a remarkably good outcome."
He added that the school's Caving Club members had acknowledged that they failed to properly follow the club's safety protocols. It was unclear, however, what exactly led to the lapse. Caving Club officers did not respond to messages sent to the club's Facebook group and also declined to comment to the IU student newspaper, citing "a sensitive legal matter."
The club's website emphasizes safety rules to follow while caving, from always carrying three sources of light per person to never going caving alone. According to local media outlets, the club published a statement to an IU student network that said Cavar's situation was the result of "a failure in our leadership."
"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 statement read. "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."
The Indiana Karst Conservancy, a nonprofit organization that owns Sullivan Cave, declined to give details about the case or how groups are allowed to access the cave.
"We have no comment on that, thank you," Julian Lewis, the conservancy's president, said by phone Saturday before hanging up.
Cavar posted a message to Facebook after he was rescued, according to the BBC: "Just wanted to let everyone know that I'm safe and sound! Just got rescued about 30 minutes ago. Boy, it's good to be back on the surface!"
He told the AP that he does not plan to go spelunking again.