Good day guys. We have an area here where some TH are having an operation. By history, it is said that there's a lot of Japanese who stayed here during WW2. And in this particular spot, we have found some signs carved in the coconut tree and some on the rocks. Under the coconut tree theres a rock with two holes and the other is having like a heart shape. Inside the two holes, there's a small stone that was like put inside. Around its corner, there's another stone having a shape that points on the side of the tree. The coconut tree has like an X sign also carved on it.
We tried a detector and it has a faint sound so we decided to dig a hole. The upper layer are stones that we think are markers and after 2 ft, it is like a limestone until the 9th feet. The bottom of the hole is now on 9 ft and we will continue on the next day.
I put a red circle on the pics to show what we think are the signs. Any ideas and interpretations with this?