What does the cay look like?

In the novel, the cay is a flat island surrounded by coral banks. On the east, the coral reefs extend several hundred yards. Upon approach, Timothy tells Phillip that he sees sea-grape bushes behind the beach and also twenty to thirty palm trees on a hill. The island is about one mile long and half a mile wide; it is shaped like a melon or a turtle. Timothy later tells Phillip that the hill will make a nice look-out for them, as it is forty feet from the sea.

When Timothy and Phillip make land, they discover that the beach is made up of fine grains of sand. Accordingly, the beach is about forty miles wide in most places, and it stretches all around the island. Timothy tells Phillip that there is plenty of pompano fish and langosta at the cay. Langosta are the native Caribbean lobsters which have no claws. Later, Timothy and Phillip are also able to feast on mussels and the eggs of sea urchins.