Gavlfjorden is a fjord (more accurately, a sound) in the municipality of Øksnes in Nordland county, Norway. The 20-kilometre (12 mi) long fjord separates the large islands of Langøya and Andøya in the Vesterålen archipelago. In the north, the fjord flows out into the Norwegian Sea, and in the south, the fjord splits into the Sortlandssundet strait and the Risøysundet strait.