Piratøen [Pirate Island]

You are pirates and at a bar last night you heard about the rumour that there is a treasure on a certain island. You took off immediately and you have just arrived on the shore of the island. You have found a cave and a ship. Maybe the ship belonged to other pirates at one point and maybe the rumours about the treasure are true? It is very likely that other pirates are on their way to the island, so you only have 1 hour to look for the treasure.