Islands and Maritime Zones
The legal regime governing islands, rocks, and artificial structures and their entitlement to maritime zones under UNCLOS.
The Island Regime
UNCLOS Article 121 establishes the legal regime for islands. Paragraph 1 defines an island as 'a naturally formed area of land, surrounded by water, which is above water at high tide.' Paragraph 2 states that islands generate the same maritime zones as other land territory: territorial sea, contiguous zone, EEZ, and continental shelf. But paragraph 3 introduces a crucial exception: 'Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf.'
This three-part structure creates enormous strategic stakes. A fully entitled island generates an EEZ of up to 200 nautical miles, covering approximately 125,000 square nautical miles of ocean. The difference between an 'island' and a 'rock' can be worth billions of dollars in fisheries and mineral resources. States have consequently invested enormous effort in maintaining, inhabiting, and even building up remote features to support island claims.