Geography is a substantial chunk ofGame of Thrones. The varied climates and topographies of Westeros and its surrounding areas change the nature of the people and events. Life in the frozen North feels alien to the freedom and pleasantries of Dorne’s arid deserts. The islands off Westeros' coasts rarely enjoy the spotlight of their landlocked neighbors, butHouse of the Dragonpays special attention to the island of Driftmark.
With their impressive budget and incredible scale,Game of ThronesandHouse of the Dragonhave some of the most beautiful shooting locations on TV. A wealthy and dedicated fan could visit Castle Ward in Northern Ireland to see Winterfell, then travel to Croatia’s Cathedral of St. James, which played theIron Bank of Braavos. Driftmark appeared inHouse of the Dragonin the form of St. Michael’s Mount near Cornwall, England, and it’s one of the best analogs to the show’s fictional locations.

What is Driftmark?
Driftmark is an island off the eastern coast of Westeros. It’s the largestisland in Blackwater Bay, an inlet of the Narrow Sea separated by the Gullet. Driftmark sits west of Dragonstone and north of Massey’s Hook, though also divided from that mainland feature by the Gullet. The island earned its name from the driftwood that regularly washes ashore. Driftmark has only a few noted settlements. Its seat of power is called High Tide, an elegant castle on a tidal island connected to Driftmark by a causeway. The smaller land mass was once only accessible during low tide, but the causeway allows travel. The old castle, also called Driftmark, was small, dark, grim, and consistently damp, leading the ruling Noble House to abandon it. Underneath Castle Driftmark, the mighty port town of Hull grew from three small fishing villages. Spicetown enjoyed a similar escalation, rising from a small hamlet to become a busy port. Driftmark is wealthy, industrious, and always active with ships fromacross the Seven Kingdoms.
Driftmark has historically been the seat of power for House Velaryon. House Velaryon traces its storied lineage to the Valyrian Freehold, bearing many genetic markers of that once-great empire’s citizens. The family left Valyria for Driftmark before House Targaryen fled their homeland and conquered Dragonstone. House Targaryen abandoned Valyria after a premonition gave them twelve years of forewarning, savingthem from the Doom. The two families had so much in common and few allies after the cataclysmic event that they bonded closely. House Velaryon was House Targaryen’s oldest ally, from their first steps on Westerosi shores to Aegon’s Conquest. While House Targaryen ruled the skies with their dragons, House Velaryon ruled the seas. Their bond spanned generations and led to a prominent place in theDance of the Dragons. In hisWorld of Ice and Fire, Maester Yandel described House Velaryon like this:

House Velaryon: a family of old and storied Valyrian heritage who had come to Westeros before the Targaryens, as the histories agree, and who often provided the bulk of the royal fleet.
Why is Driftmark significant?
House of the Dragoncovers theDance of the Dragons, a landmark civil war between two descendants of King Viserys I Targaryen. Battles broke out between firstborn daughter Rhaenyra and her younger half-brother Aegon II. Lord Corlys Velaryon was the head of his House as the Dance began. He married into House Targaryen in 90 AC, tying down Rhaenys Targaryen, the Queen Who Never Was. Rhaenys was second-in-line for the Iron Throne when her father died. King Jaehaerys I selected his second son over Rhaenys, the rightful heir. Corlys was so furious he gave up his admiralty and position on the small council. When his and Rhaenys' daughter, Laena, entered another succession election, she was passed over too. Having seen two rightful heirs cheated out of their position because of their gender, Corlys Velaryon became the most powerful lord to support Rhaenyra in theDance of the Dragons.
Driftmark provided naval supremacy during the Dance. As the war started, Velaryon ships blockaded the Gullet and cut off access to Blackwater Bay. After several defeats,Ser Otto Hightowerallied with the Triarchy to break House Velaryon’s blockade. Though it took some time, this led to the Battle of the Gullet, the bloodiest naval conflict in the Known World. The losses were tremendous on both sides. A third of the Velaryon fleet was sunk. The Triarchy technically won, though they suffered logistical blows so great they would never recover. During the conflict, Triarchy forces bypassed Dragonstone, choosing to sack Driftmark. They burned High Tide and Spicetown to the ground. Driftmark would never rebuild Spicetown, but the island’s participation in the war was largely over.
Driftmark is a key location in the Dance of the Dragons but rarely mentioned inGame of Thrones. Corlys Velaryon’s tremendous wealth made the island powerful, but its involvement in world events remained rare. It’s only acknowledged once in the main bookswhen Davos Seaworthsails past its distinctive point. In some ways, House Velaryon and Driftmark were better off without participating in the story. They had their fill of conflict in the Dance.