Question: What island is part of the Islands of Furness and has a castle that was used as a base by the Yorkist pretender Lambert Simnel in 1487?
Sentence (from "Piel Island"): Piel Island lies half a mile (1 km) off the southern tip of the Furness Peninsula in the administrative county of Cumbria, though historically within Lancashire north of the sands.
Relevant evidence: Yes