The sinkhole she found was narrow, but it seemed she could crawl through it. She helped the professor to the lower opening of the sinkhole’s chimney, then crawled into the narrow cavity. She fit comfortably, tying two ropes around her waist—one end to the professor’s waist, the other to her bag—and began climbing upward.

“Are you sure you’ve thought this through?” the old man asked as they set off. She nodded. They didn’t have enough food or water to last days, and she was also worried about the professor, who was running a fever. This wasn’t the first tough situation she had been in during her work or studies. Both she and the professor were used to tight spaces. If there was even a sliver of hope they could get out this way, they would try.
When she mentioned the passage to the professor, the old man began to explain.

“That, my dear, is a sinkhole that leads to the lowest chamber. The cave wasn’t first explored where you and I came down. This cave was discovered by the professor who taught me hydrogeology at university, nearly forty years ago. He descended through this sinkhole into what was then the lowest known chamber.”

“And why didn’t you tell me about this earlier?” she asked. She wasn’t angry, but perhaps they wouldn’t have been stuck here for hours if the old man had mentioned it sooner. The professor raised an eyebrow.

“I never tried that passage myself. The cave’s discoverer said he only descended through it and made his way up through the route we came down. I don’t know if it’s still passable.” They would find out together.