anchor: After all, the waters of the Canary Islands, only 445 km (275 miles) to the south, had occupied busy shipping lanes for very nearly a century, and Genovese maps from the mid-14th century depict both Madeira and Porto Santo.
positive: The waters of the Canary islands is only 445km.
negative: The Canary Islands have been occupied by busy shipping lanes for its entire lifespan.