Porto Santo Island

Porto Santo Island ) is a Portuguese island 43 kilometres northeast of Madeira Island in the North Atlantic Ocean; it is the northernmost and easternmost island of the archipelago of Madeira, located in the Atlantic Ocean west of Europe and Africa.

It appears that some knowledge of Atlantic islands, such as Madeira, existed before the discovery and settlement of these lands, as the islands appear on maps as early as 1339. From a portolan dating to 1351, and preserved in Florence, Italy, it would appear that the islands of Madeira had been discovered long before being claimed by the Portuguese expedition of 1418. In Libro del Conocimiento , a Castilian monk also identified the location of the islands in their present location, with the names Leiname , Diserta and Puerto Santo. Indeed, the move by Portugal to claim the Madeiran islands was probably a response to Spain's efforts at the time to claim and subdue the Canary Islands.

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