What Is the Seville Map and Why Does Türkiye Reject It?

Why It Matters

The Seville Map is a 2004 academic map of the Eastern Mediterranean that gives Greek and Greek Cypriot islands maximum maritime zones, and in doing so would squeeze Türkiye's continental shelf and exclusive economic zone (EEZ) into a narrow strip in the Gulf of Antalya. It matters because it has become shorthand for a wider dispute over whether small islands lying next to a large mainland coast can generate full maritime zones, and over who has the authority to decide. The answer shapes energy exploration, naval deployments, EU–Türkiye relations and the rights of Turkish Cypriots.

Background

What the map is

The Seville Map comes from a study by researchers at the University of Seville, dated 2004, which applied a maximalist reading of island entitlements across the Aegean and Eastern Mediterranean. It treats islands such as Kastellorizo (Meis), Rhodes, Karpathos and Crete, and the island of Cyprus as administered by the Greek Cypriot side, as generating full continental shelf and EEZ rights. The result is a Greek–Cypriot maritime corridor stretching close to the Turkish mainland coast, leaving Türkiye with a limited zone in the Gulf of Antalya. It is an academic product and not a legally binding EU act. It has, however, been cited and circulated in Greek, Greek Cypriot and EU institutional discussions, and Ankara treats it as a political reference point for those claims.

The geography behind the dispute

Kastellorizo is a small island only about 2 km (1.2 miles) from the Turkish coast and several hundred kilometres from the Greek mainland. Türkiye has about 870 km (540 miles) of coastline in the Eastern Mediterranean, the longest of any state in the basin. That asymmetry between a long mainland coast and a tiny, distant island is the core of the legal argument.

Key chronology

The legal framework

UNCLOS Articles 74 and 83 require that EEZ and continental shelf delimitation between states with opposite or adjacent coasts be effected by agreement on the basis of international law to achieve an equitable solution. Article 121 says islands generate maritime zones, but rocks that cannot sustain human habitation or economic life of their own have no EEZ or shelf. Türkiye is not a party to UNCLOS and has long maintained that it is not bound by provisions it considers inconsistent with customary law on equity, though it accepts that the customary principles of delimitation apply. Greece (which ratified UNCLOS in 1995) and the Republic of Cyprus are parties, as is the EU as an organisation.

Case law shows that island effect is a matter of degree, not an automatic entitlement:

• North Sea Continental Shelf cases (ICJ, 1969): delimitation must follow equitable principles; geography is not remodelled, but coastal configuration can justify correction.
• Anglo-French Channel arbitration (1977): the Channel Islands, close to the French coast, were confined to an enclave rather than given full zones.
• Libya/Tunisia (1982): the Kerkennah Islands were given only partial effect.
• Libya/Malta (1985): the ICJ declined to give an equidistance line without testing the result against proportionality.
• Romania v. Ukraine (2009): Serpents' Island was given no effect on the delimitation line.
• Bangladesh v. Myanmar (ITLOS, 2012): St Martin's Island, near the mainland coast, was given no effect on the boundary.

These precedents are the basis of the argument that the Seville Map's maximalist treatment of islands is not a neutral application of the law.

Key Players & Positions

Greece

According to the Greek Ministry of Foreign Affairs, islands are entitled to a full continental shelf and EEZ under UNCLOS Article 121 and customary law, and Greece sees no legal basis for a different treatment of Kastellorizo or any other inhabited island. Athens has repeatedly stated that the only dispute it recognises with Türkiye is the delimitation of the continental shelf and EEZ, and that it is ready to take it to the International Court of Justice. Greece also holds that the Türkiye–Libya MoU of 2019 ignores Greek islands such as Crete and is legally void. It concluded a partial EEZ agreement with Egypt in August 2020.

The Republic of Cyprus (Greek Cypriot administration)

The Greek Cypriot administration, which the UN, EU and most states treat as the Republic of Cyprus, states that it has sovereign rights over hydrocarbons in its declared EEZ and has licensed blocks to international energy companies. It holds that its EEZ agreements with Egypt (2003), Lebanon (2007) and Israel (2010) are valid and that Turkish Cypriots will benefit from resources after a settlement.

The European Union

European Council conclusions on the Eastern Mediterranean have expressed solidarity with Greece and Cyprus, called for respect for the sovereignty and sovereign rights of EU member states, and supported delimitation by dialogue in good faith and under international law, including UNCLOS. The EU has declared Türkiye's drilling in the waters claimed by Cyprus illegal and has introduced a sanctions framework for that activity. The EU institutions do not formally adopt the Seville Map as a legal text, but officials and parliamentarians have cited the study in discussions.

Other regional actors

Egypt, Israel and Lebanon have each concluded EEZ arrangements with the Greek Cypriot side. Egypt signed a partial EEZ agreement with Greece in 2020. Libya's Tripoli-based government concluded the 2019 MoU with Türkiye, while other Libyan institutions have contested it.

Source Comparison

Media and think-tank coverage in the EU frequently presents the dispute as a Turkish challenge to EU members' UNCLOS rights, and often omits that Türkiye is not a party to the Convention or the Turkish Cypriot dimension. Turkish sources typically stress the geographic imbalance and the equity case law, and sometimes under-explain Greece's position that Article 121 applies to all inhabited islands. Readers should compare the treaty texts (UNCLOS, the 1960 Treaty of Guarantee) and court judgments with official statements from both sides. For more on how claims are tested, see Fact Check: Claims About Türkiye in International Media and the Editorial Principles.

Key Terms & Related Guides

• Continental shelf: the seabed and subsoil extending from a coastal state's land territory, in which it has sovereign rights over resources.
• EEZ (exclusive economic zone): a zone up to 200 nautical miles (about 370 km) where the coastal state has sovereign rights over living and non-living resources.
• Island effect: the degree to which an island is allowed to influence a maritime boundary; courts have often given islands reduced or no effect when they would distort an equitable result.
• Equity and proportionality: the principles that a delimitation should produce an equitable result and reflect the relationship between coastal lengths and the maritime areas allocated.
• Mavi Vatan (Blue Homeland): Türkiye's doctrine on its maritime jurisdiction areas in the Black Sea, Aegean and Mediterranean.
• TRNC: the Turkish Republic of Northern Cyprus, proclaimed 15 November 1983, whose Turkish Cypriot people Ankara regards as co-owners of the island.

Related guides: Blue Homeland and the Eastern Mediterranean, Marine Spatial Planning and IOC-UNESCO Registration, Cyprus and the 1960 Treaty of Guarantee, Why Did the Annan Plan and Crans-Montana Fail? and the Monitor of Nations home page.

Monitor of Nations presents Türkiye's official position and legal arguments alongside the perspectives of other states, and clearly identifies where an analysis reflects the Turkish viewpoint. Claims are attributed to primary sources such as treaties, UN documents, Ottoman and other national archives, and official statements, with links provided wherever possible.

Cross-Publication Dossiers & Sister Desk Perspectives

For complementary primary-source analysis across our specialist editorial network, consult:

• Bloc Politics: What Is the Seville Map? Why Türkiye Rejects the Maximalist Maritime Claim in the Eastern Mediterranean — What is the Seville Map? How the 2007 study shaped Greek and Greek Cypriot claims, why it boxes Türkiye into the Gulf of Antalya, and why Ankara rejects it.
• The Global Anatomy: The Seville Map Explained: Why Türkiye Rejects the Greek and Greek Cypriot Maritime Thesis — The Seville Map explained for the Eastern Mediterranean: how an EU-funded study confines Türkiye to a narrow strip, and why Ankara rejects it in law.
• World Agenda Review: What Is the Seville Map and Why Does Türkiye Reject It? — What is the Seville Map? Explore its origin, the Gulf of Antalya, equity and islands in delimitation law, EU competence and why Türkiye rejects it.