Which islands separate the Strait of Magellan from mainland South America?

The Strait of Magellan separates the South American shores from the Tierra del Fuego islands, which are located south of the mainland. At these latitudes, the weather is very unstable, severe storms often occur, which is why, from the moment of opening and after a long time, many ships crashed on the rocky shores of the archipelago. Although nominally these territories belonged to Spain since the 16th century, but due to poor climatic conditions and low productivity of these lands, European settlers could not settle there for a long time.