The Sunset Sea is roamed by swordfish, seals, and whales, and Ironman's Bay and coastal regions are populated by various fish and shellfish. The north of the sea contains krakens, leviathans, and possibly legendary sea dragons.
In the south, the Redwyne Straits and the Arbor divide the Sunset Sea from the Summer Sea to the southeast. North of the Arbor is Whispering Sound with Oldtown, Blackcrown, and Three Towers. Farther north in the Reach along the Sunset Sea are Bandallon, the Shield Islands, and the mouth of the Mander.
Beyond the Iron Islands is a peninsula of the north which includes the Flint Cliffs, Cape Kraken, and Flint's Finger. The Fever River and the Saltspear flow into Blazewater Bay. North of the peninsula are the coastlines of the Rills and the Stony Shore. Even further to the north are the Bay of Ice and the forests of Bear Island, Sea Dragon Point, and the wolfswood. The Sunset Sea continues north beyond the Wall along the Frozen Shore.
In Songs the Drowned Men Sing, Maester Kirth suggested that the Seastone Chair was created by a people from west of the Sunset Sea, and Archmaester Haereg proposed that the ironborn of the Iron Islands descend from these visitors.
The ironborn of antiquity used their longships to dominate the western coast of Westeros, initially raiding the First Men of the green lands but eventually turning to conquest in the era of driftwood kings. During the reign of Qhored Hoare the ironborn controlled the western shore of Westeros from the Arbor to Bear Island, but his gains were gradually lost by his descendants. The First Men of the continent eventually fought back with longships of their own and used stone fortifications to defend against the raiders, and skilled Andal sailors accelerated the ironborn's fall.
Thousands of years ago, Brandon the Shipwright, King in the North, tried to sail across the Sunset Sea but was never heard from again. His son, Brandon the Burner, destroyed the northern shipyards in his grief.
Claiming the riverlands, King Arlan III Durrandon extended the borders of the Kingdom of the Storm from the narrow sea in the east to the Sunset Sea in the west. However, his descendant, Arrec, lost the riverlands to Harwyn Hoare, King of the Isles and the Rivers.
In 56 AC Elissa Farman, Ser Eustace Hightower, and Ser Norman Hightower sailed west from Oldtown to discover what is beyond the Sunset Sea. Autumn Moon sank during a storm, with some on Eustace's Lady Meredith claiming they saw a kraken attack Norman's ship. Elissa's Sun Chaser discovered the uninhabited islands Aegon, Rhaenys, and Visenya. While Eustace chose to return to Westeros, Elissa continued exploring west but was never seen again. Years later, Corlys Velaryon believed that he saw Sun Chaser in Asshai.
Lord Alton Greyjoy, known as the Holy Fool, attempted to conquer lands beyond the Lonely Light. Lord Dalton Greyjoy, the Red Kraken, ruled much of the Sunset Sea during the Dance of the Dragons until his murder at Fair Isle. Lord Dagon Greyjoy also attempted to make the lands along the sea subject to the ironborn again, but was eventually defeated by House Targaryen.
A Clash of Kings
A Feast for Crows
During the kingsmoot, Gylbert Farwynd, Lord of the Lonely Light, puts his name forth for King of the Iron Islands, supported by three champions who are his sons. He promises to lead the ironborn to lands beyond the Sunset Sea where every man would be a king, but his claims are quickly dismissed.
No one has ever crossed the Sunset Sea to learn what lies on the other side.
—thoughts of Theon Greyjoy
- A Game of Thrones, Chapter 25, Eddard V.
- A Storm of Swords, Chapter 14, Catelyn II.
- The World of Ice & Fire, The Iron Islands.
- Fire & Blood, Jaehaerys and Alysanne - Their Triumphs and Tragedies.
- The World of Ice & Fire, The Iron Islands: Driftwood Crowns.
- The Lands of Ice and Fire.
- So Spake Martin: Trade with Asshai, August 26, 2000
- Fire & Blood, The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain.
- The World of Ice & Fire, Ancient History: The Dawn Age.
- A Game of Thrones, Appendix.
- The World of Ice & Fire, The Iron Islands: The Iron Kings.
- A Game of Thrones, Chapter 66, Bran VII.
- The World of Ice & Fire, The Stormlands: Andals in the Stormlands.
- The World of Ice & Fire, The Reign of the Dragons: The Conquest.
- The World of Ice & Fire, Dorne: Dorne Against the Dragons.
- The World of Ice & Fire, The Iron Islands: The Old Way and the New.
- The World of Ice & Fire, The Iron Islands: The Red Kraken.
- A Dance with Dragons, Chapter 63, Victarion I.
- A Feast for Crows, Chapter 19, The Drowned Man.
- A Feast for Crows, Chapter 29, The Reaver.
- A Clash of Kings, Chapter 11, Theon I.