If I'm not mistaken, while you're in the cave you read/hear of a message that says something like "The eye sees something valuable".
Find the whale's eye and dig below it!
This was when Jim found the treasure map at the inn, and their voyage starts to Treasure Island
yes, treasure island has treasure. when the crew reaches treasure island they think that it is gone. but ben gunn has been taking the treasure to a cave.
When you go to Molidas Island there is a house in the north east corner of the island where there is a cave. After talking to a woman she lets you inside. In the cave after you go through some stuff there is a place with a table, jar and a treasure chest. Open it.
You must gain permission from Ramonos (in the hut next to the cave entrance) to enter the cave. You will find a secret hideout in the cave with a treasure chest containing the shovel that belongs to a fisherman.
The cave on Mercay Island is featured on the series of The Legend of Zelda Nintendo games. This game was developed in Japan, and its most recent game release was in August of 2014.
Wayfarers cave on Molidia Island
Ben Gunn from Treasure Island
Use the shovel. You get it on Molidia Island inside the Wayfarers cave.
The Treasure Cave is in Mountain Falls Which is Hidden Behind a Giant Boulder. You Will Have to Destroy the Boulder To Get In The Treasure Cave
there are palm trees on the top of the island (excludes cave) dig under them
you go to the island below the fog and find a map in a cave that tells you how
Go in the hidden cave underground on that island where you got the shovel. In there, there will be a map on the wall showing you how to get through.