For the two women and one man trapped in the darkness of an old West Virginia coal mine with no food or water, four days felt like 10.

They heard yells and sounds that they thought might be people banging on the tracks, but they weren't sure.

"We could hear them, but you know we would scream at the top of our lungs, and I guess they just couldn't hear us — we was too far away," said Cody Beverly, 21, one of the three rescued Wednesday evening from the Rock House Powellton mine in Clear Creek.

"We thought we was honestly hallucinating," he said Thursday of the four days they spent trapped underground.

Beverly, Kayla Williams, Erica Treadway and Eddie Williams entered the inactive mine, which has not been mined for coal in two years, on Saturday and were reported missing late that night.

Kayla Williams, left, and Erica Treadway after they were discharged from the hospital and rescued from a mine in West Virginia on Dec. 12, 2018. NBC News

Williams was able to make his way out of the mine, promising to return with help for the other three. He emerged late Monday and told authorities the rest were alive, officials said.

Although Beverly, Williams and Treadway were trapped for four days, it felt longer.

“I thought we was underground for 10, 11 days,” Beverly said. “I mean, it seemed like it had been that long.”

With no water, the trio took a chance and drank from a stream running down the tracks, Beverly said. They found some old bottles to collect water, and because the stream was running and not stagnated, they thought it would be OK to drink, Treadway said.

"We didn't drink much of it, because we were concerned about iron and lead poisoning and contamination, but we drank what we could, just to stay alive," she said.

Mine rescuers pumped out water and used fans to pump in fresh air during the search.

"When they finally turned the fans on, it was just like a sign of relief,” Beverly said. “Like, you could finally breathe again. You know what I mean?"

The air quality was so compromised, they could move only about 15 feet from where they were hunkered down.

"That's as far as we could make it," he said. "You were collapsing."

The first of the three were found about 6 p.m. Wednesday, and the other two about a half-hour later, said Eugene White, director of the West Virginia Office of Miners' Health, Safety and Training.

All four are under criminal investigation but have not been charged, a sheriff’s official said.

Entering a closed mine is illegal, no matter what the foursome intended to do there, said Raleigh County sheriff’s Lt. M.A. McCray.

The mother of one of the three rescued Wednesday has said she believes they were in the mine to steal copper.

Beverly denied that the group was looking for copper. He said they were simply exploring and "coal mining."

"You can’t get away from this scot-free," Beverly said to NBC News. "I’ll take my penalties, I’ll go along with it. I’ll move along and be a better person for it."

Treadway also said they were just exploring, but she understands why some might think otherwise since people do enter mines to steal copper.

“We didn’t go in there to do that, we went in there to have fun,” she said.

The experience has left some of the survivors with a new perspective. Treadway, a mother of three, said she never gave up hope that she would survive.

"I felt like God brought me to it, and God will bring me through it," she said. "And so I knew that I wasn't to die in that hole.

"I knew that I had a bigger cause than to lay there and give up," she continued. "And my kids kept me going — the thought of my friends laying in there, perishing away. I couldn’t do that. I had to be strong for them.”

All three received medical treatment after they were rescued.

"We should have never went underground. It was a stupid mistake. We thought we was coal mining. I thought it was fun," Beverly said. "Once we realized that we was lost, we wasn't coal mining no more. It wasn’t fun, it was surreal."

Beverly said the ordeal has inspired him to be a better man.

"It was a life-changing experience," he said, adding that family members have warned him in the past that if he kept acting foolishly, he could pay a serious price.

Beverly said he's grateful to the rescuers, to his friends and to be home with his family.

"My family said that they’re going to wrap me up under the tree," he said. "They said I’m the Christmas present this year."