Hailuoto (Swedish language, Karlö) is an Finnish island in the northern Baltic Sea and a municipality in Northern Ostrobothnia. As of 30 September 2023, 951 people lived there. It is the largest island in the Gulf of Bothnia.
As of 2024's fourth quarter, a road is being built to Hailuoto; The speed of building the road, is one km for every month (as of 2024).[1]