What is a peninsula?

The word peninsula is derived from the Latin pene meaning 'almost' and insula meaning 'island'. While it could be said that a peninsula is "almost an island", in reality this is not the case.

A peninsula is a long strip of land that juts out into the sea, e.g. southern Thailand. It is usually surrounded by water on three sides, or two of three sides if it is triangular-shaped.

Other examples include the state of Florida (USA), the Kenai Peninsula of Alaska (USA) and the Leelanau Peninsula of Michigan (USA). Even the Scandinavian countries of Norway and Sweden could be argued to occupy a large peninsula. The Iberian Peninsula contains the entire country of Spain.

However, the term doesn't refer to a particular scale, nor the size of the surrounding body of water. There are peninsulas in small lakes as well as large seas. Whilst some definitions state that a peninsula is a region of land connected to the mainland by an isthmus, this is not necessarily true either. The Eyre, Yorke and Fleurieu Peninsulas in South Australia, for example, are broadest where they connect to the land and taper to a narrow point. Cape York Peninsula in north Queenland is a huge tract of land, initially broad and narrowing gradually to its tip.