Madre de Dios Island (Spanish: Isla Madre de Dios) is an island in the Patagonian Archipelago in Magallanes y la Antártica Chilena Region, Chile. Its area is 1,043 km². Madre de Dios Island is composed partly by limestone and has several natural caves. In one of those caves called the "Cave of the whales" skelletons of ancient whales were discovered 10 to 30 meters above the sea level.
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