Osterøy is an island situated northeast of the city of Bergen in Vestland county, Norway. With a total area of 328 square kilometres, it is the largest Norwegian island not located directly adjacent to the ocean, and the second largest such island in Northern Europe. Osterøy is covered by two municipalities: the majority by Osterøy municipality, and the rest by Vaksdal municipality. The vast majority of the island's population lives in Osterøy municipality.