What are the two main features of the island in treasure island

The island does not look pleasant or welcoming.

There all hands were already congregated. A belt of fog had lifted almost simultaneously with the appearance of the moon. Away to the south-west of us we saw two low hills, about a couple of miles apart, and rising behind one of them a third and higher hill, whose peak was still buried in the fog. All three seemed sharp and conical in figure.

So much I saw, almost in a dream, for I had not yet recovered from my horrid fear of a minute or two before. And then I heard the voice of Captain Smollett issuing orders. The Hispaniola was laid a couple of points nearer the wind and now sailed a course that would just clear the island on the east. ch 12