Hovedøya is one of several small islands off the coast of Oslo, Norway in the Oslofjord. The island is quite small, no more than 800 metres across in any direction, the total area is 0,4 square kilometre. It is well known for its lush and green nature, with a wide variety of trees, bushes and flowers. For many, many years there was a military base on the island.
== The name ==
The name is from Norse times (Hǫfudøy). The first element is hǫfud 'head' (here in the sense 'hill' or 'height'), the last element is the finite form of øy 'island'.