I managed to open the cursed book! One of the pages contained a map of an island called Sacra Terra. I went to the docks and found a fisherman who owned a small boat. He told me Sacra Terra is located several miles away from shore and said ships won't go near it. Sailors say strange things happen there and are afraid of what might happen to them. Regardless, I convinced the fisherman to take me there, although I had to promise I wouldn't stay long.