C425 Underwater Tomb

"Uncle, do you still remember where that place is? If you see it, will you be able to find it? " I asked.

The old man nodded and said, "Of course I know that. That place is at the customs station. It is one day south of here. Jump down."

"Uncle, please speak clearly. What is the flight range?" "How far is the one-day voyage? Can you tell me?" I asked anxiously.

The old man turned over