The concept of maritime zones is a cornerstone of international maritime law, defined primarily by the United Nations Convention on the Law of the Sea (UNCLOS). These zones determine the extent of a coastal state’s rights, responsibilities, and jurisdiction over the waters and resources adjacent to its shores.

Background
• Maritime zones were established to resolve disputes over navigation, resource ownership, and national security.
• Boundaries are measured from a country’s baseline (usually the low-water mark along the coast).
• The key zones include:
• Internal Waters – full sovereignty like land territory.
• Territorial Sea – up to 12 nautical miles.
• Contiguous Zone – up to 24 nautical miles.
• Exclusive Economic Zone (EEZ) – up to 200 nautical miles.
• Continental Shelf – may extend beyond 200 nautical miles depending on natural features.

Purpose
• Internal Waters – treated like land territory, full state control.
• Territorial Sea (12 nm) – authority over navigation, resources, and law enforcement.
• Contiguous Zone (24 nm) – enforcement against smuggling, illegal entry, and security threats.
• Exclusive Economic Zone (200 nm) – exclusive rights to explore and exploit resources (fish, oil, gas).
• Continental Shelf – rights over seabed resources even beyond EEZ.

Importance
• Safeguards national security and territorial sovereignty.
• Ensures sustainable use of marine resources (fisheries, oil, gas).
• Provides control over shipping routes and trade lifelines.
• Strengthens sovereignty in disputed waters (vital for nations like the Philippines).
• Globally, reduces conflict, promotes order and cooperation, and protects the marine environment.