Seiland

thumb | right | Rocky beaches of Seiland

or is a substantial island off Norway's northern coast, covering about . It is the eighth largest island in Norway proper, located in Finnmark county. It sits within the Caledonian orogenic zone, a mountain‑building belt formed during the Paleozoic. The southern and western parts of the island consist mainly of gabbroic rocks, marking the northeastern end of a basic petrographic province that extends more than 100 km to the southwest. The island is divided between the Alta and Hammerfest municipalities.