Understanding International Waters: Boundaries, Jurisdiction and Legal Implications

The seas and oceans are divided into different areas, each with its own legal framework and effects. The high seas, also known as the high seas. Play an important role in international law, shipping, and also resource extraction. Establishing boundaries and international waters distance around the high seas is essential to ensuring orderly conduct and fostering global cooperation.

Territorial Sea 

The territorial sea is an area adjacent to the land of a coastal state. It extends up to an 12 nautical miles (22.2 kilometres) from the baseline. Which is the low-tide line along the coast. Within this zone, coastal states are exercise full sovereignty. Including to the right to regulate and enforce customs, immigration, and environmental protection laws. The United Nations Convention on the Law of the Sea (UNCLOS) that provides the legal framework for territorial waters.

Inland Waters 

Inland waters refer to baseline coastal waters, such as bays, rivers, lakes, and also canals. Which are under the jurisdiction of all or part of a coastal state. Coastal states have full sovereignty over these waters, including the right to formulate and enforce laws and regulations. The extent of an inland waters is determined by national laws and international agreements.

Contiguous Zone 

A contiguous zone is an area adjacent to territorial waters. That extends up to 24 nautical miles (44.4 kilometres) from the baseline. In this zone, coastal states have limited controls to prevent and also punish violations of customs, taxes, immigration, and sanitary regulations. However, the jurisdiction of coastal states within the contiguous zone does not extend to shipping and overflight issues. UNCLOS forms the legal basis for the contiguous zone.

Continental Shelf 

Continental Shelf means the subsoil of the ocean floor and undersea areas that extend more than 200 nautical miles beyond to the territorial Sea and are a natural extension of the landmass of a coastal state. Coastal states have sovereignty over the exploration and exploitation of a natural resources, both living and non-living, within their continental shelves. The outer boundaries of the continental shelf are determined by scientific and technical research.

Continental Slope 

A continental slope is an area of ​​the ocean floor that rapidly increases in depth across the continental shelf toward the deep ocean floor. Although continental slopes are not defined as separate oceanic zones, they are geologically and ecologically important. Coastal states may have special rights and obligations in the area related to scientific research, environmental protection, and resource exploration.

Exclusive Economic Zone (EEZ) 

The EEZ is the area adjacent to the territorial Sea of ​​a coastal state extending up to 200 nautical miles which means (370.4 kilometres) from the baseline. Within the EEZ, coastal states have sovereignty and jurisdiction over natural resources, which are both living (such as fish and other marine life) and non-living (such as gas, oil, and minerals). Coastal states also have a responsibility to protect and manage these resources.UNCLOS provides the legal framework for EEZs.

High Seas 

The high seas, also known as the high seas, are areas of the world’s oceans that are outside the jurisdiction of any particular country. These waters are open to all countries, and the principle of “freedom of the high seas” applies. Nations and individuals enjoy freedoms such as navigation, fishing, overflight, and laying undersea cables. UNCLOS provides to the legal framework for the high seas, including regulations regarding piracy, pollution, and the protection of marine resources.

Regulation And Other Aspects Of The High Seas: Where Do The High Seas Start?

When do international waters start ? International waters distance, also known as the high seas, are areas of the world’s oceans that are outside the jurisdiction of any particular country. They exist outside the territorial Sea and adjacent waters of a coastal state. The beginning of international waters distance, is generally considered to be where a country’s territorial sea ends, usually 12 nautical miles from the baselines of the coastal State. This principle is enshrined in Article 3 of the United Nations Convention on the Law of the Sea (UNCLOS). 

How Far from the Coast are the High Seas 

The generally accepted international waters distance, is 12 nautical miles (about 22.2 kilometres) from a country’s coastal baselines. This distance is based on the principle of territorial Sea in customary international law, which gives coastal states certain rights and an jurisdiction over a defined area extending from their coasts. The exact measurements may vary depending on domestic laws and bilateral agreements.

Distances in International Waters 

As mentioned above, international waters begin beyond the 12 nautical mile limit from a country’s coastal baseline. These zones extend to the international waters distance, of the exclusive economic zone (EEZ), usually up to 200 nautical miles from the coastal baseline or to the outer limits of the continental shelf, whichever is farther. The specific boundaries and limits of the EEZ and continental shelf are determined based on the provisions of UNCLOS and relevant bilateral or multilateral agreements.

Can we do Anything on the High Seas?

The high seas are governed by the concept of “freedom of the high seas,” which provides certain freedoms and rights to states and individuals. Article 87(1) of the 1982 Convention explicitly enumerates the following freedoms on the high seas: 

  1. Freedom of Navigation.
  2. Freedom of overflight.
  3. Freedom to lay submarine cables and pipelines.
  4. Freedom to construct artificial islands and other facilities recognized by international law.
  5. Freedom to fish.
  6. Freedom of scientific research.

Please note that a ship cannot change its flag while at Sea or in port. (Article 92, Paragraph 1). Each State shall effectively exercise its jurisdiction and control in administrative, technical and social matters over ships flying its flag as provided for in Article 94(1) of the Convention on the Law of the Sea.

What Happens if a Crime is Committed on the High Seas?

Crimes committed on the high seas present unique legal challenges. Generally, crimes committed on board ships on the high seas fall under the jurisdiction of the flag state, that is, the country under whose laws the ship is registered. This principle is codified in various laws and statutes, including flag state jurisdiction law and the law of the Sea. However, many countries exercise universal jurisdiction over certain serious crimes, such as an piracy, drug trafficking, and terrorism, and can prosecute individuals regardless of their nationality or flag.

What is Illegal on the High Seas?

Certain activities are generally considered illegal on the high seas. These include drug trafficking, piracy, human trafficking, illegal fishing, illegal dumping of dangerous goods, and also involvement in acts of violence and terrorist attacks. International conventions and treaties such as UNCLOS, the International Convention for the Suppression of the Financing of Terrorism, and the Convention against Transnational Organized Crime provide the legal framework to combat such crimes. Additionally, domestic laws of coastal states and international agreements may further regulate certain activities in.

International Tribunal for the Law of the Sea (ITLOS) 

After the entry into force of his UNCLOS in 1994, significant efforts were made towards the establishment to the International Tribunal for the Law of the Sea (ITLOS). ITLOS is an intergovernmental organization established on behalf of the Third United Nations Conference on the Law of the Sea. It was established by the United Nations Convention on the Law of the Sea, signed in Montego Bay, Jamaica, on December 10, 1982. ITLOS was finally established on October 21, 1996, and its jurisdiction is non-compulsory, voluntary, or based on state consent.

 Some famous maritime disputes 

1. Dispute Over Squid on the High Seas Between Chile and Peru: 

Chile and Peru have long been in dispute over the management and also exploitation of squid resources in the Humboldt Current on the high seas. The dispute primarily revolves around different interpretations of maritime boundaries and the impact of each country’s fishing practices on their shared squid populations.

2. Turbot War between Spain and Canada: 

In the 1990s, Spain and Canada were involved in a high-seas conflict known as the Turbot War. The dispute erupted when a Spanish trawler was accused of overfishing flounder in international waters off the coast of Newfoundland, Canada. Canada responded by seizing a Spanish fishing boat, leading to heightened tensions and also diplomatic confrontations between the two countries.

3. The Northern Territories Dispute between Japan and Russia: 

Japan and Russia have a territorial dispute over the Kuril Islands in the North Pacific Ocean. The disagreement concerns issues of fishing rights and also access to the rich marine resources around the island. The conflict has affected bilateral relations and hindered cooperation in the region.


Understanding the legal aspects of the international waters distance is critical to fostering maritime cooperation. Ensuring maritime security and also combating criminal activity in these regions. Boundaries, permitted activities, legal challenges and legal implications. Related to the high seas are governed by international treaties, national laws and also bilateral/multilateral agreements. Compliance with this legal framework is critical to maintaining peace. Security on the high seas and sustainable use of marine resources.

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