The Thousand Islands were among the remote waters explored by Corlys Velaryon on the Sea Snake’s third voyage. His passage through them made him the first Westerosi to navigate the islands, extending his travels beyond the familiar routes of the western seas into the Shivering Sea.

Setting and Recorded Voyage

The Thousand Islands appear in the account of Corlys’s third voyage aboard the Sea Snake. Rather than returning to the eastern route he had taken on earlier expeditions, Corlys tried the Shivering Sea. He became the first Westerosi to navigate the Thousand Islands and continued on to visit the bleak, cold shores of N’ghai and Mossovy.

Place in Corlys Velaryon’s Voyages

The passage through the islands forms part of a sequence of increasingly distant voyages. On earlier journeys, Corlys had sailed beyond Qarth to Yi Ti and Leng, and later reached Asshai-by-the-Shadow; the third voyage turned north instead. The Thousand Islands therefore mark not a destination described in isolation, but a notable stage in the Sea Snake’s exploration of unfamiliar waters.

Significance

The account identifies the islands chiefly through the achievement of navigating them: Corlys was the first Westerosi to do so. Their sparse description contrasts with the concrete distinction attached to the voyage, making the Thousand Islands a measure of how far his seafaring carried him beyond the known routes of Westeros.