With an area of 8.9 square kilometers (3.4 sq mi), it is the largest island in the municipality.

'Herøy Strait'),[1] which is crossed by the Herøysund Bridge and Norwegian County Road 828 to the neighboring island of Sør-Herøy.

To the northwest is the island of Hestøya, with bridge connections to the nearby islands of Indre Øksningan, Ytre Øksningan, Staulen, and Seløya, and to the Åkviksundet Bridge to Dønna.

The municipal seat, Silvalen, is located on the island along Herøysundet.

[1] There are three lakes on the island: Storvatnet, Salsvatnet, and Vikvatnet.