Li Youqian came to visit and inspected it carefully and found that this was indeed a trace left by man!

It is an arrow-shaped, as if giving people guidance.%d7%cf%d3%c4%b8%f3

"Can anyone have been here before?" Li Youqian guessed to himself.

"Looking at it, this mark should be a little old." Feng Nian said after rubbing the arrow-shaped mark several times.

"It took us nearly eight minutes to swim from the beginning. Even if we can hold our breath alone, we can't swim here, right?" Li Youqian's face was even more confused. This culvert is no better than the river outside. It's okay to dive dozens of meters outside. However, here, the undercurrents at the bottom of the water are surging, and the waterways are complex and changeable. At least three times more effort than the river outside. Maybe accidents will occur at the bottom of the culvert.

"Mr. Li, you have overlooked a very important issue." Feng Nian smiled, then pointed to a layer of dead black and brown moss on the cave, "Look at this."

"What's wrong?" Li Youqian asked in confusion.

"The moss here is divided into layers, and it can be judged that the water level in the culvert is not static. Based on these dead mosses, it can be seen that the cave should have been completely submerged at the peak of the water level, but at the low point, it may have to go down one or two meters." Feng Nian explained.

Then they dived into the water again and found that there was a layer of moss that had died on the rock wall more than one meter below the water surface.

If we look at this lowest water level, during a certain dry season, there should be a section above the entire hibernation, so that others can float on it and swim in from outside without worrying about being drowned.

"Mr. Li, since there is a mark here, it means that someone should have entered here many years ago. But even in the anti-drying period, the inside of the culvert should be full of dangers. Most people should not come here with their lives, right? In this way, those who sneak in here must have other more important purposes so that they can be willing to take such a big risk." Feng Nian speculated.

"Do you think someone is hiding a treasure inside this culvert?" Li Youqian suddenly realized that it was not difficult to see through the various signs that there was really a possibility.

"Yes, let's look forward according to this mark, and it is very likely that we will find the treasure!" Feng Nian said excitedly.

"Then let's look forward to see if we can find other marks." When Li Youqian thought of the treasure, he became excited.

Originally, they were just trying to detect the amount of water in the culvert, but no one expected that there would be such an unexpected discovery.

After putting on the diving suit again, Li Youqian and the others swam forward along the culvert.

Not to mention, after swimming about twenty meters, they actually found the same mark on the rock wall.

The two of them were energetic and continued to explore forward. Before they knew it, the two hundred meters of rope came to the end.

"This culvert is really deep. If we want to explore further, we must go outside and get a rope in it." Feng Nian said to Li Youqian via radio.
Chapter completed!